Datasets:
christopher
/
oeis

Dataset card Data Studio Files
xet
Community
2
sequence_id
stringlengths
7
7
sequence_name
stringlengths
4
573
sequence
sequencelengths
1
348
keywords
sequencelengths
1
8
score
int64
1
2.31k
offset_a
int64
-14,827
666,262,453B
offset_b
int64
0
635M
⌀
cross_references
sequencelengths
1
128
⌀
former_ids
sequencelengths
1
3
⌀
author
stringlengths
7
231
⌀
timestamp
timestamp[us]date
1999-12-11 03:00:00
2025-04-28 00:58:08
filename
stringlengths
29
29
hash
stringlengths
32
32
A001201
Number of Steiner triple systems (STS's) on 6n+1 or 6n+3 elements.
[ "1", "1", "30", "840", "1197504000", "60281712691200", "1348410350618155344199680000" ]
[ "nonn", "nice", "hard", "more" ]
28
0
3
[ "A001201", "A030128", "A030129", "A047241", "A051390" ]
[ "M5214", "N2268" ]
N. J. A. Sloane
2022-06-17T03:23:17
oeisdata/seq/A001/A001201.seq
151c1cf323f8fba1d64e36b9691a0b08
A001202
a(1)=0, a(2n) = a(n)+1, a(2n+1) = 10*a(n+1).
[ "0", "1", "10", "2", "100", "11", "20", "3", "1000", "101", "110", "12", "200", "21", "30", "4", "10000", "1001", "1010", "102", "1100", "111", "120", "13", "2000", "201", "210", "22", "300", "31", "40", "5", "100000", "10001", "10010", "1002", "10100", "1011", "1020", "103", "11000", "1101", "1110", "112", "1200", "121", "130", "14", "20000", "2001", "2010" ]
[ "nonn", "easy" ]
19
1
3
null
null
N. J. A. Sloane
2022-09-08T08:44:28
oeisdata/seq/A001/A001202.seq
dfc805d030f40b313d1f1d717df4e0d9
A001203
Simple continued fraction expansion of Pi.
[ "3", "7", "15", "1", "292", "1", "1", "1", "2", "1", "3", "1", "14", "2", "1", "1", "2", "2", "2", "2", "1", "84", "2", "1", "1", "15", "3", "13", "1", "4", "2", "6", "6", "99", "1", "2", "2", "6", "3", "5", "1", "1", "6", "8", "1", "7", "1", "2", "3", "7", "1", "2", "1", "1", "12", "1", "1", "1", "3", "1", "1", "8", "1", "1", "2", "1", "6", "1", "1", "5", "2", "2", "3", "1", "2", "4", "4", "16", "1", "161", "45", "1", "22", "1", "2", "2", "1", "4", "1", "2", "24", "1", "2", "1", "3", "1", "2", "1" ]
[ "nonn", "nice", "cofr" ]
162
0
1
[ "A000796", "A001203", "A007541", "A033089", "A033090", "A097545", "A097546" ]
[ "M2646", "N1054" ]
N. J. A. Sloane
2025-03-15T16:34:28
oeisdata/seq/A001/A001203.seq
d1a65a9fe230444e3630c4fa15bef96c
A001204
Continued fraction for e^2.
[ "7", "2", "1", "1", "3", "18", "5", "1", "1", "6", "30", "8", "1", "1", "9", "42", "11", "1", "1", "12", "54", "14", "1", "1", "15", "66", "17", "1", "1", "18", "78", "20", "1", "1", "21", "90", "23", "1", "1", "24", "102", "26", "1", "1", "27", "114", "29", "1", "1", "30", "126", "32", "1", "1", "33", "138", "35", "1", "1", "36", "150", "38", "1", "1", "39", "162", "41", "1", "1", "42", "174", "44", "1", "1", "45", "186", "47", "1", "1" ]
[ "nonn", "easy", "cofr", "nice" ]
44
0
1
[ "A001204", "A003417", "A004273", "A005131", "A058282", "A072334" ]
[ "M4322", "N1811" ]
N. J. A. Sloane
2023-12-30T15:59:33
oeisdata/seq/A001/A001204.seq
7c6ca5014a8d6208020077746bca38b4
A001205
Number of clouds with n points; number of undirected 2-regular labeled graphs; or number of n X n symmetric matrices with (0,1) entries, trace 0 and all row sums 2.
[ "1", "0", "0", "1", "3", "12", "70", "465", "3507", "30016", "286884", "3026655", "34944085", "438263364", "5933502822", "86248951243", "1339751921865", "22148051088480", "388246725873208", "7193423109763089", "140462355821628771", "2883013994348484940" ]
[ "nonn", "easy", "nice" ]
87
0
5
[ "A000985", "A000986", "A001205", "A002137", "A059441", "A144163" ]
[ "M2937", "N1181" ]
N. J. A. Sloane
2022-03-31T08:58:01
oeisdata/seq/A001/A001205.seq
3d29f0b36f43c9e8e7d75d79f4f74595
A001206
Number of self-dual monotone Boolean functions of n variables.
[ "0", "1", "2", "4", "12", "81", "2646", "1422564", "229809982112", "423295099074735261880" ]
[ "nonn", "hard", "nice", "more" ]
105
0
3
[ "A000372", "A001206", "A006126", "A007363", "A014466", "A051185", "A059090", "A305844", "A326361", "A326362", "A326363", "A326366", "A326372" ]
[ "M1267", "N0486" ]
N. J. A. Sloane
2025-02-18T08:58:49
oeisdata/seq/A001/A001206.seq
3a57a1138134f732798174ad45d0d936
A001207
Number of fixed hexagonal polyominoes with n cells.
[ "1", "3", "11", "44", "186", "814", "3652", "16689", "77359", "362671", "1716033", "8182213", "39267086", "189492795", "918837374", "4474080844", "21866153748", "107217298977", "527266673134", "2599804551168", "12849503756579", "63646233127758", "315876691291677", "1570540515980274", "7821755377244303", "39014584984477092", "194880246951838595", "974725768600891269", "4881251640514912341", "24472502362094874818", "122826412768568196148", "617080993446201431307", "3103152024451536273288", "15618892303340118758816", "78679501136505611375745" ]
[ "nonn", "nice" ]
53
1
2
[ "A000228", "A001207", "A006535", "A059716", "A121220" ]
[ "M2897", "N1162" ]
N. J. A. Sloane
2024-08-31T09:51:34
oeisdata/seq/A001/A001207.seq
1992bcde54ea1498dd6699ef23a53b86
A001208
a(n) = solution to the postage stamp problem with 3 denominations and n stamps.
[ "3", "8", "15", "26", "35", "52", "69", "89", "112", "146", "172", "212", "259", "302", "354", "418", "476", "548", "633", "714", "805", "902", "1012", "1127", "1254", "1382", "1524", "1678", "1841", "2010", "2188", "2382", "2584", "2801", "3020", "3256", "3508", "3772", "4043", "4326", "4628", "4941", "5272", "5606", "5960", "6334", "6723", "7120" ]
[ "nonn", "nice" ]
50
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A195618", "A196416" ]
[ "M2721", "N1351" ]
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001208.seq
abe7661b51c98ae796aec9b83614d84b
A001209
a(n) is the solution to the postage stamp problem with 4 denominations and n stamps.
[ "4", "12", "24", "44", "71", "114", "165", "234", "326", "427", "547", "708", "873", "1094", "1383", "1650", "1935", "2304", "2782", "3324", "3812", "4368", "5130", "5892", "6745", "7880", "8913", "9919", "11081", "12376", "13932", "15657", "17242", "18892", "21061", "23445", "25553", "27978", "31347", "33981", "36806", "39914", "43592" ]
[ "nonn" ]
48
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196069", "A196416" ]
[ "M3432", "N1568" ]
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001209.seq
02b5785a56d23631fe4d0f51beb6b5b4
A001210
a(n) is the solution to the postage stamp problem with 5 denominations and n stamps.
[ "5", "16", "36", "70", "126", "216", "345", "512", "797", "1055", "1475", "2047", "2659", "3403", "4422", "5629", "6865", "8669", "10835", "12903", "15785", "18801", "22456", "26469", "31108", "36949", "42744", "49436", "57033", "66771", "75558", "86303", "96852", "110253", "123954", "140688", "158389", "178811", "197293", "223580" ]
[ "nonn" ]
42
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196416" ]
[ "M3864", "N1707" ]
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001210.seq
2fcdd75d023ee23f25ef32c0fc4c59c3
A001211
a(n) is the solution to the postage stamp problem with 6 denominations and n stamps.
[ "6", "20", "52", "108", "211", "388", "664", "1045", "1617", "2510", "3607", "5118", "7066", "9748", "12793", "17061", "22342", "28874", "36560", "45745", "57814", "72997", "87555", "106888", "129783" ]
[ "nonn", "more" ]
40
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196416" ]
[ "M4136", "N1836" ]
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001211.seq
2a5bd71c1be1aed67bd9f900976f119a
A001212
a(n) = solution to the postage stamp problem with n denominations and 2 stamps.
[ "2", "4", "8", "12", "16", "20", "26", "32", "40", "46", "54", "64", "72", "80", "92", "104", "116", "128", "140", "152", "164", "180", "196", "212" ]
[ "nonn", "nice", "more" ]
103
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A006638", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A123509", "A196094", "A196416", "A234941" ]
[ "M1089", "N0972" ]
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001212.seq
b1e3df2ad13435f49903e3d008e510c9
A001213
a(n) is the solution to the postage stamp problem with n denominations and 3 stamps.
[ "3", "7", "15", "24", "36", "52", "70", "93", "121", "154", "186", "225", "271", "323", "385", "450", "515", "606", "684", "788", "865", "977", "1091", "1201", "1361" ]
[ "nonn", "more" ]
36
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196416" ]
[ "M2647", "N1340" ]
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001213.seq
abec97e341e747dbd4114008f7d9552d
A001214
a(n) is the solution to the postage stamp problem with n denominations and 4 stamps.
[ "4", "10", "26", "44", "70", "108", "162", "228", "310", "422", "550", "700", "878", "1079", "1344", "1606", "1944", "2337", "2766", "3195", "3668", "4251", "4923", "5631", "6429" ]
[ "nonn", "more" ]
44
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196416" ]
[ "M3391", "N1559" ]
N. J. A. Sloane
2023-01-13T21:12:48
oeisdata/seq/A001/A001214.seq
f1a1d24a45e4dacbb8374e2f6f7e6f8f
A001215
a(n) is the solution to the postage stamp problem with n denominations and 5 stamps.
[ "5", "14", "35", "71", "126", "211", "336", "524", "726", "1016", "1393", "1871", "2494", "3196", "4063", "5113", "6511", "7949", "9865", "11589" ]
[ "nonn", "more" ]
44
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196416" ]
[ "M3845", "N1706" ]
N. J. A. Sloane
2022-02-03T02:27:42
oeisdata/seq/A001/A001215.seq
946b20b67af42695c0ca5600b425d65e
A001216
a(n) = solution to the postage stamp problem with n denominations and 6 stamps.
[ "6", "18", "52", "114", "216", "388", "638", "1007", "1545", "2287" ]
[ "nonn", "more" ]
36
1
1
[ "A001208", "A001209", "A001210", "A001211", "A001212", "A001213", "A001214", "A001215", "A001216", "A005342", "A005343", "A005344", "A014616", "A053346", "A053348", "A075060", "A084192", "A084193", "A196416" ]
[ "M4120", "N1831" ]
N. J. A. Sloane
2020-08-14T13:45:07
oeisdata/seq/A001/A001216.seq
506c67bbf2bfd5788546d87b76b4c62f
A001217
Sorted list of orders of Weyl groups of types A_n, B_n, D_n, E_n, F_4, G_2.
[ "1", "2", "4", "6", "8", "12", "24", "48", "120", "192", "384", "720", "1152", "1920", "3840", "5040", "23040", "40320", "46080", "51840", "322560", "362880", "645120", "2903040", "3628800", "5160960", "10321920", "39916800", "92897280", "185794560", "479001600", "696729600", "1857945600", "3715891200" ]
[ "nonn", "easy", "nice" ]
15
1
2
null
null
N. J. A. Sloane
2019-07-12T02:27:44
oeisdata/seq/A001/A001217.seq
2a626f928c76a694e137f3b81602d238
A001218
a(n) = 3^n mod 100.
[ "1", "3", "9", "27", "81", "43", "29", "87", "61", "83", "49", "47", "41", "23", "69", "7", "21", "63", "89", "67", "1", "3", "9", "27", "81", "43", "29", "87", "61", "83", "49", "47", "41", "23", "69", "7", "21", "63", "89", "67", "1", "3", "9", "27", "81", "43", "29", "87", "61", "83", "49", "47", "41", "23", "69", "7", "21", "63", "89", "67" ]
[ "nonn", "easy" ]
29
0
2
[ "A001148", "A001218", "A216096", "A216097" ]
null
N. J. A. Sloane
2024-07-30T02:49:48
oeisdata/seq/A001/A001218.seq
fb1f35e71dd2817e15139c9105e397da
A001219
Triangular numbers of form a(a+1)(a+2).
[ "0", "6", "120", "210", "990", "185136", "258474216" ]
[ "nonn", "fini", "full" ]
22
1
2
[ "A000217", "A001219", "A097571" ]
null
N. J. A. Sloane
2025-02-16T08:32:22
oeisdata/seq/A001/A001219.seq
d040dd26b8fab8b6eb8d075c627f3c28
A001220
Wieferich primes: primes p such that p^2 divides 2^(p-1) - 1.
[ "1093", "3511" ]
[ "nonn", "hard", "bref", "nice", "more", "changed" ]
366
1
1
[ "A001008", "A001220", "A001567", "A002323", "A007540", "A014127", "A039951", "A045616", "A049094", "A077816", "A088164", "A090968", "A111027", "A123692", "A123693", "A126196", "A126197", "A128667", "A128668", "A128669", "A178815", "A178844", "A178871", "A178900", "A212583", "A234810", "A242741", "A242982", "A244260", "A246503", "A247208", "A269798", "A298951", "A306255", "A306256" ]
null
N. J. A. Sloane
2025-04-22T10:47:39
oeisdata/seq/A001/A001220.seq
6a36709a0ab25a6167911291059e27f3
A001221
Number of distinct primes dividing n (also called omega(n)).
[ "0", "1", "1", "1", "1", "2", "1", "1", "1", "2", "1", "2", "1", "2", "2", "1", "1", "2", "1", "2", "2", "2", "1", "2", "1", "2", "1", "2", "1", "3", "1", "1", "2", "2", "2", "2", "1", "2", "2", "2", "1", "3", "1", "2", "2", "2", "1", "2", "1", "2", "2", "2", "1", "2", "2", "2", "2", "2", "1", "3", "1", "2", "2", "1", "2", "3", "1", "2", "2", "3", "1", "2", "1", "2", "2", "2", "2", "3", "1", "2", "1", "2", "1", "3", "2", "2", "2", "2", "1", "3", "2", "2", "2", "2", "2", "2", "1", "2", "2", "2", "1", "3", "1", "2", "3", "2", "1", "2", "1", "3", "2" ]
[ "nonn", "easy", "nice", "core" ]
199
1
6
[ "A000010", "A001221", "A001222", "A005063", "A005064", "A005065", "A008472", "A008683", "A013939", "A046660", "A069010", "A069359", "A087624", "A091202", "A091221", "A125666", "A143519", "A144494", "A156542", "A156552", "A158210", "A285577", "A322078", "A346617", "A351193", "A351194", "A351195", "A351196", "A351197", "A351198", "A351242", "A351244", "A351245", "A351246", "A351247", "A351248", "A351249", "A351262" ]
[ "M0056", "N0019" ]
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001221.seq
54c6a3b6cf591f44a4a241cefd0197dd
A001222
Number of prime divisors of n counted with multiplicity (also called big omega of n, bigomega(n) or Omega(n)).
[ "0", "1", "1", "2", "1", "2", "1", "3", "2", "2", "1", "3", "1", "2", "2", "4", "1", "3", "1", "3", "2", "2", "1", "4", "2", "2", "3", "3", "1", "3", "1", "5", "2", "2", "2", "4", "1", "2", "2", "4", "1", "3", "1", "3", "3", "2", "1", "5", "2", "3", "2", "3", "1", "4", "2", "4", "2", "2", "1", "4", "1", "2", "3", "6", "2", "3", "1", "3", "2", "3", "1", "5", "1", "2", "3", "3", "2", "3", "1", "5", "4", "2", "1", "4", "2", "2", "2", "4", "1", "4", "2", "3", "2", "2", "2", "6", "1", "3", "3", "4", "1", "3", "1", "4", "3", "2", "1", "5", "1", "3", "2" ]
[ "nonn", "easy", "nice", "core" ]
220
1
4
[ "A000010", "A000040", "A000120", "A001221", "A001222", "A001358", "A008836", "A014612", "A014613", "A014614", "A020639", "A022559", "A027748", "A046306", "A046308", "A046310", "A046312", "A046314", "A046660", "A066829", "A069272", "A069273", "A069274", "A069275", "A069276", "A069277", "A069278", "A069279", "A069280", "A069281", "A073093", "A074946", "A079149", "A086436", "A091202", "A091222", "A091304", "A092248", "A134334", "A144494", "A156552", "A267116", "A268387" ]
[ "M0094", "N0031" ]
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001222.seq
13deb8ad3d6bd888905eeca59fd062c3
A001223
Prime gaps: differences between consecutive primes.
[ "1", "2", "2", "4", "2", "4", "2", "4", "6", "2", "6", "4", "2", "4", "6", "6", "2", "6", "4", "2", "6", "4", "6", "8", "4", "2", "4", "2", "4", "14", "4", "6", "2", "10", "2", "6", "6", "4", "6", "6", "2", "10", "2", "4", "2", "12", "12", "4", "2", "4", "6", "2", "10", "6", "6", "6", "2", "6", "4", "2", "10", "14", "4", "2", "4", "14", "6", "10", "2", "4", "6", "8", "6", "6", "4", "6", "8", "4", "8", "10", "2", "10", "2", "6", "4", "6", "8", "4", "2", "4", "12", "8", "4", "8", "4", "6", "12" ]
[ "nonn", "nice", "easy", "hear", "changed" ]
331
1
2
[ "A000040", "A000230", "A000720", "A001223", "A001248", "A005250", "A005669", "A007921", "A008347", "A028334", "A029707", "A029709", "A030173", "A031131", "A031165", "A031166", "A031167", "A031168", "A031169", "A031170", "A031171", "A031172", "A036263", "A036274", "A037201", "A038664", "A080378", "A104120", "A167770", "A174349", "A320701", "A320720", "A330556", "A330561" ]
[ "M0296", "N0108" ]
N. J. A. Sloane
2025-04-21T16:03:10
oeisdata/seq/A001/A001223.seq
926a82182c69388d808020a658f0edbd
A001224
If F(n) is the n-th Fibonacci number, then a(2n) = (F(2n+1) + F(n+2))/2 and a(2n+1) = (F(2n+2) + F(n+1))/2.
[ "1", "2", "2", "4", "5", "9", "12", "21", "30", "51", "76", "127", "195", "322", "504", "826", "1309", "2135", "3410", "5545", "8900", "14445", "23256", "37701", "60813", "98514", "159094", "257608", "416325", "673933", "1089648", "1763581", "2852242", "4615823", "7466468", "12082291", "19546175", "31628466" ]
[ "nonn", "nice", "easy" ]
146
1
2
[ "A001224", "A060312", "A068928", "A102526" ]
[ "M0318", "N0117" ]
N. J. A. Sloane
2022-12-06T10:00:07
oeisdata/seq/A001/A001224.seq
ede469fbf4db14f74483686a8d9322d0
A001225
Number of consistent arcs in a tournament with n nodes.
[ "1", "2", "5", "7", "11", "14", "20", "24", "30", "35", "44", "50" ]
[ "nonn", "nice", "hard", "more" ]
39
2
2
[ "A001225", "A003141" ]
[ "M1333", "N0510" ]
N. J. A. Sloane
2021-08-28T02:53:48
oeisdata/seq/A001/A001225.seq
63190b286c55fe0afd54d8ea96b17d22
A001226
Lerch's function q_2(n) = (2^{phi(t)} - 1)/t where t = 2*n - 1.
[ "1", "1", "3", "9", "7", "93", "315", "17", "3855", "13797", "195", "182361", "41943", "9709", "9256395", "34636833", "31775", "479349", "1857283155", "430185", "26817356775", "102280151421", "372827", "1497207322929", "89756051247", "84215045", "84973577874915", "19991120505", "1205604855", "4885260612740877" ]
[ "nonn" ]
21
1
3
[ "A000010", "A001226" ]
null
N. J. A. Sloane
2017-12-19T02:23:04
oeisdata/seq/A001/A001226.seq
79bf6d93665eb3f477f352d3d197f6fd
A001227
Number of odd divisors of n.
[ "1", "1", "2", "1", "2", "2", "2", "1", "3", "2", "2", "2", "2", "2", "4", "1", "2", "3", "2", "2", "4", "2", "2", "2", "3", "2", "4", "2", "2", "4", "2", "1", "4", "2", "4", "3", "2", "2", "4", "2", "2", "4", "2", "2", "6", "2", "2", "2", "3", "3", "4", "2", "2", "4", "4", "2", "4", "2", "2", "4", "2", "2", "6", "1", "4", "4", "2", "2", "4", "4", "2", "3", "2", "2", "6", "2", "4", "4", "2", "2", "5", "2", "2", "4", "4", "2", "4", "2", "2", "6", "4", "2", "4", "2", "4", "2", "2", "3", "6", "3", "2", "4", "2", "2", "8" ]
[ "nonn", "easy", "nice", "mult", "core" ]
350
1
3
[ "A000005", "A000079", "A000203", "A000593", "A001227", "A001620", "A002162", "A010054", "A038547", "A050999", "A051000", "A051001", "A051002", "A051731", "A053866", "A054844", "A055932", "A060831", "A066311", "A069283", "A069288", "A073485", "A073491", "A107428", "A109814", "A115369", "A118235", "A118236", "A125911", "A136655", "A137921", "A183063", "A183064", "A237593", "A247795", "A272887", "A273401", "A279387", "A286001", "A327276", "A333217", "A356224", "A356841", "A356845", "A356956" ]
null
N. J. A. Sloane
2025-03-17T08:38:22
oeisdata/seq/A001/A001227.seq
cd1ead63def10734ada52b9bb2a5a794
A001228
Orders of sporadic simple groups.
[ "7920", "95040", "175560", "443520", "604800", "10200960", "44352000", "50232960", "244823040", "898128000", "4030387200", "145926144000", "448345497600", "460815505920", "495766656000", "42305421312000", "64561751654400", "273030912000000", "51765179004000000", "90745943887872000", "4089470473293004800", "4157776806543360000", "86775571046077562880", "1255205709190661721292800", "4154781481226426191177580544000000", "808017424794512875886459904961710757005754368000000000" ]
[ "nonn", "fini", "nice", "full" ]
26
1
1
[ "A001034", "A001228", "A005180" ]
null
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001228.seq
0215f8786b883430e22db59a5af14588
A001229
Numbers k such that phi(sigma(k)) = k.
[ "1", "2", "8", "12", "128", "240", "720", "6912", "32768", "142560", "712800", "1140480", "1190400", "3345408", "3571200", "5702400", "14859936", "29719872", "50319360", "118879488", "2147483648", "3889036800", "4389396480", "21946982400", "47416320000", "92177326080", "133145026560", "331914240000", "460886630400", "665725132800" ]
[ "nonn" ]
71
1
2
[ "A000010", "A001229", "A018784", "A135240", "A373435", "A373453", "A373454" ]
null
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001229.seq
b745fd54574689c1d612c37653ed16ff
A001230
Number of undirected closed knight's tours on a 2n X 2n chessboard.
[ "0", "0", "9862", "13267364410532" ]
[ "nonn", "hard", "more", "nice" ]
57
1
3
[ "A001230", "A165134" ]
null
N. J. A. Sloane, Martin Loebbing (loebbing(AT)ls2.informatik.uni-dortmund.de), Brendan McKay
2025-02-16T08:32:23
oeisdata/seq/A001/A001230.seq
2a55c2149b19a10bb239297ef4a6b1bb
A001231
Number of nonisomorphic projective planes of order n.
[ "1", "1", "1", "1", "0", "1", "1", "4", "0" ]
[ "nonn", "hard", "more", "nice" ]
29
2
8
null
null
N. J. A. Sloane.
2025-02-16T08:32:23
oeisdata/seq/A001/A001231.seq
71c15646e881e428aee27508a5d7b36d
A001232
Numbers k such that 9*k = (k written backwards), k > 0.
[ "1089", "10989", "109989", "1099989", "10891089", "10999989", "108901089", "109999989", "1089001089", "1098910989", "1099999989", "10890001089", "10989010989", "10999999989", "108900001089", "108910891089", "109890010989", "109989109989", "109999999989", "1089000001089", "1089109891089" ]
[ "base", "nonn", "nice" ]
117
1
1
[ "A001232", "A002275", "A002283", "A004086", "A008918", "A008919", "A031877", "A094707", "A124074", "A193434", "A222814", "A222815" ]
null
N. J. A. Sloane and Simon Plouffe
2025-01-09T10:09:07
oeisdata/seq/A001/A001232.seq
35cee894d3716664d20d6346951d1419
A001233
Unsigned Stirling numbers of first kind s(n,6).
[ "1", "21", "322", "4536", "63273", "902055", "13339535", "206070150", "3336118786", "56663366760", "1009672107080", "18861567058880", "369012649234384", "7551527592063024", "161429736530118960", "3599979517947607200", "83637381699544802976", "2021687376910682741568", "50779532534302850198976", "1323714091579185857760000" ]
[ "nonn", "easy" ]
57
6
2
[ "A000254", "A000399", "A000454", "A000482", "A001233", "A001234", "A008275", "A243569", "A243570" ]
[ "M5114", "N2216" ]
N. J. A. Sloane
2025-02-24T09:13:33
oeisdata/seq/A001/A001233.seq
5e7d464c6c34f5f1f66a314cfcf51f2e
A001234
Unsigned Stirling numbers of the first kind s(n,7).
[ "1", "28", "546", "9450", "157773", "2637558", "44990231", "790943153", "14409322928", "272803210680", "5374523477960", "110228466184200", "2353125040549984", "52260903362512720", "1206647803780373360", "28939583397335447760" ]
[ "nonn", "easy" ]
45
7
2
[ "A000254", "A000399", "A000454", "A000482", "A001233", "A001234", "A008275", "A243569", "A243570" ]
[ "M5202", "N2264" ]
N. J. A. Sloane
2022-02-03T00:28:08
oeisdata/seq/A001/A001234.seq
770f46712965957def213105e2beaca4
A001235
Taxi-cab numbers: sums of 2 cubes in more than 1 way.
[ "1729", "4104", "13832", "20683", "32832", "39312", "40033", "46683", "64232", "65728", "110656", "110808", "134379", "149389", "165464", "171288", "195841", "216027", "216125", "262656", "314496", "320264", "327763", "373464", "402597", "439101", "443889", "513000", "513856", "515375", "525824", "558441", "593047", "684019", "704977" ]
[ "nonn", "nice", "changed" ]
138
1
1
[ "A001235", "A003325", "A003825", "A003826", "A007692", "A008917", "A011541", "A018786", "A018787", "A018850", "A023050", "A023051", "A051167", "A051347", "A155057", "A343708", "A360619" ]
null
N. J. A. Sloane
2025-04-23T07:07:21
oeisdata/seq/A001/A001235.seq
4a1e251191ff85b37943097b84994a4a
A001236
Differences of reciprocals of unity.
[ "15", "575", "46760", "6998824", "1744835904", "673781602752", "381495483224064", "303443622431870976", "327643295527342080000", "466962174913357393920000", "858175477913267353681920000", "1993920215002599923346309120000", "5758788816015998806424467537920000" ]
[ "nonn" ]
30
1
1
[ "A000254", "A000424", "A001236", "A001237", "A001238", "A008969" ]
[ "M4993", "N2149" ]
N. J. A. Sloane
2020-04-28T11:51:37
oeisdata/seq/A001/A001236.seq
5dfbe220cd4675946580dd5362c79b0a
A001237
Differences of reciprocals of unity.
[ "31", "3661", "1217776", "929081776", "1413470290176", "3878864920694016", "17810567950611972096", "129089983180418186674176", "1409795030885143760732160000", "22335321387514981111936450560000", "497400843208278958640564703068160000", "15161356456130244705175927906904309760000" ]
[ "nonn" ]
39
1
1
[ "A001237", "A008969" ]
[ "M5229", "N2276" ]
N. J. A. Sloane
2024-07-30T02:53:08
oeisdata/seq/A001/A001237.seq
61d9367d258e62c39573ee46504d43ae
A001238
Differences of reciprocals of unity.
[ "63", "22631", "30480800", "117550462624", "1083688832185344", "21006340945438768128", "778101042571221893382144", "51150996584622542869024997376", "5626686079269855254796985958400000", "987233834003503822099304377378406400000" ]
[ "nonn" ]
28
1
1
[ "A001238", "A008969" ]
[ "M5328", "N2316" ]
N. J. A. Sloane
2023-12-22T08:35:23
oeisdata/seq/A001/A001238.seq
2ac6807e4ad69b7b658dd574fbaf21ab
A001239
Numbers that are the sum of 3 nonnegative cubes in more than 1 way.
[ "216", "251", "344", "729", "855", "1009", "1072", "1366", "1457", "1459", "1520", "1674", "1728", "1729", "1730", "1737", "1756", "1763", "1793", "1854", "1945", "2008", "2072", "2241", "2414", "2456", "2458", "2729", "2736", "2752", "3060", "3391", "3402", "3457", "3500", "3592", "3599", "3655", "3744", "3745" ]
[ "nonn" ]
31
1
1
[ "A001235", "A001239", "A003998", "A008917", "A025396", "A025447", "A025456" ]
null
N. J. A. Sloane
2022-05-21T13:59:22
oeisdata/seq/A001/A001239.seq
d9cd5212575f3d65a5c3b59456680df3
A001240
Expansion of 1/((1-2x)(1-3x)(1-6x)).
[ "1", "11", "85", "575", "3661", "22631", "137845", "833375", "5019421", "30174551", "181222405", "1087861775", "6528756781", "39177307271", "235078159765", "1410511939775", "8463200647741", "50779591044791", "304678708005925" ]
[ "nonn", "easy", "nice" ]
61
1
2
[ "A001240", "A008969", "A021029", "A112492" ]
[ "M4798", "N2049" ]
N. J. A. Sloane
2022-04-13T13:25:15
oeisdata/seq/A001/A001240.seq
1212e64c6402288ad98592393ee602b2
A001241
Differences of reciprocals of unity.
[ "1", "50", "1660", "46760", "1217776", "30480800", "747497920", "18139003520", "437786795776", "10536798272000", "253246254177280", "6082300519393280", "146028165842661376", "3505313580591718400", "84135194495708938240", "2019336829962040279040" ]
[ "nonn", "easy" ]
33
1
2
[ "A001241", "A008969", "A028037", "A112492" ]
[ "M5301", "N2305" ]
N. J. A. Sloane
2023-06-25T02:31:54
oeisdata/seq/A001/A001241.seq
3371af9781f5578629b1e262e8913158
A001242
Differences of reciprocals of unity.
[ "1", "274", "48076", "6998824", "929081776", "117550462624", "14500866102976", "1765130436471424", "213373597575314176", "25700650466807540224", "3089923562153380965376", "371145495540181143169024", "44558899569395347436056576", "5348360831598738338465357824" ]
[ "nonn", "easy" ]
21
1
2
[ "A001242", "A008969", "A103878", "A112492" ]
[ "M5433", "N2362" ]
N. J. A. Sloane
2015-06-13T00:48:03
oeisdata/seq/A001/A001242.seq
50b96bb61cedad9b854c721ea2a7b7ca
A001243
Eulerian numbers (Euler's triangle: column k=7 of A008292, column k=6 of A173018).
[ "1", "247", "14608", "455192", "9738114", "162512286", "2275172004", "27971176092", "311387598411", "3207483178157", "31055652948388", "285997074307300", "2527925001876036", "21598596303099900", "179385804170146680" ]
[ "nonn", "easy" ]
59
7
2
[ "A000012", "A000460", "A000498", "A000505", "A000514", "A001243", "A008292", "A173018" ]
[ "M5422", "N2355" ]
N. J. A. Sloane, Mira Bernstein, Robert G. Wilson v
2024-12-30T17:03:17
oeisdata/seq/A001/A001243.seq
bac01093eb804089f17c0afb511cfe31
A001244
Eulerian numbers (Euler's triangle: column k=8 of A008292, column k=7 of A173018).
[ "1", "502", "47840", "2203488", "66318474", "1505621508", "27971176092", "447538817472", "6382798925475", "83137223185370", "1006709967915228", "11485644635009424", "124748182104463860", "1300365805079109480", "13093713503185076040" ]
[ "nonn", "easy" ]
71
8
2
[ "A000012", "A000460", "A000498", "A000505", "A000514", "A001243", "A001244", "A008292", "A123125", "A173018" ]
[ "M5457", "N2366" ]
N. J. A. Sloane, Mira Bernstein, and Robert G. Wilson v
2025-01-04T22:47:26
oeisdata/seq/A001/A001244.seq
c21505717538b7daffd766c0652e161e
A001245
Numbers that are the sum of 4 cubes in more than 1 way.
[ "81", "126", "128", "216", "217", "219", "224", "243", "251", "252", "259", "278", "280", "315", "341", "343", "344", "345", "352", "371", "376", "378", "405", "408", "432", "434", "467", "469", "496", "522", "540", "559", "560", "567", "584", "593", "594", "648", "687", "702", "728", "729", "730", "737", "756", "758", "763", "765", "783", "793", "802" ]
[ "nonn" ]
14
1
1
[ "A001235", "A001245", "A004826" ]
null
N. J. A. Sloane
2022-02-02T00:06:34
oeisdata/seq/A001/A001245.seq
59e5610f8c21890cedc4d2eb38ef5265
A001246
Squares of Catalan numbers.
[ "1", "1", "4", "25", "196", "1764", "17424", "184041", "2044900", "23639044", "282105616", "3455793796", "43268992144", "551900410000", "7152629313600", "93990019574025", "1250164827828900", "16807771574144100", "228138727737690000", "3123219182728976100", "43087676888260976400", "598598221893939680400", "8369059450146650049600" ]
[ "nonn", "easy", "nice" ]
116
0
3
[ "A000108", "A000356", "A000891", "A001246", "A008828", "A186264", "A209805" ]
null
N. J. A. Sloane
2024-06-13T11:38:31
oeisdata/seq/A001/A001246.seq
2ea9041f0c65b292185dd8fa8cd2d6e1
A001247
Squares of Bell numbers.
[ "1", "1", "4", "25", "225", "2704", "41209", "769129", "17139600", "447195609", "13450200625", "460457244900", "17754399678409", "764214897046969", "36442551140059684", "1912574337188517025", "109833379421325769609", "6866586647633870998416", "465228769500062060333281" ]
[ "nonn", "easy" ]
34
0
3
[ "A000110", "A001247" ]
null
N. J. A. Sloane
2022-09-08T08:44:28
oeisdata/seq/A001/A001247.seq
1257598698e6211f2c91055da936953f
A001248
Squares of primes.
[ "4", "9", "25", "49", "121", "169", "289", "361", "529", "841", "961", "1369", "1681", "1849", "2209", "2809", "3481", "3721", "4489", "5041", "5329", "6241", "6889", "7921", "9409", "10201", "10609", "11449", "11881", "12769", "16129", "17161", "18769", "19321", "22201", "22801", "24649", "26569", "27889", "29929", "32041", "32761", "36481" ]
[ "nonn", "easy" ]
221
1
1
[ "A000005", "A000040", "A000430", "A001248", "A001358", "A001694", "A002033", "A005408", "A005722", "A006254", "A008864", "A024450", "A033273", "A048272", "A049001", "A051709", "A059956", "A060800", "A062799", "A069482", "A078898", "A082020", "A085548", "A087112", "A095874", "A168565", "A190641", "A192134", "A211110", "A258599" ]
null
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001248.seq
7b47b6b3d383beed07a9f032b38e903f
A001249
Squares of tetrahedral numbers: a(n) = binomial(n+3,n)^2.
[ "1", "16", "100", "400", "1225", "3136", "7056", "14400", "27225", "48400", "81796", "132496", "207025", "313600", "462400", "665856", "938961", "1299600", "1768900", "2371600", "3136441", "4096576", "5290000", "6760000", "8555625", "10732176", "13351716", "16483600", "20205025", "24601600", "29767936", "35808256" ]
[ "nonn", "easy" ]
86
0
2
[ "A000290", "A000292", "A000579", "A001249", "A001303", "A006542", "A008459", "A033455", "A040977", "A086020", "A108674" ]
null
N. J. A. Sloane
2024-11-09T17:28:24
oeisdata/seq/A001/A001249.seq
0c62a2ee7e6e7dbb4d669c1d01d62bb9
A001250
Number of alternating permutations of order n.
[ "1", "1", "2", "4", "10", "32", "122", "544", "2770", "15872", "101042", "707584", "5405530", "44736512", "398721962", "3807514624", "38783024290", "419730685952", "4809759350882", "58177770225664", "740742376475050", "9902996106248192", "138697748786275802", "2030847773013704704", "31029068327114173810" ]
[ "nonn" ]
156
0
3
[ "A000041", "A000111", "A001250", "A001251", "A001252", "A001253", "A003242", "A010026", "A010094", "A025047", "A032020", "A049774", "A056986", "A104345", "A211318", "A260786", "A261962", "A325534", "A325535", "A335452", "A344614", "A344615", "A344652", "A344653", "A344654", "A344740", "A345164", "A345165", "A345167", "A345168", "A345170", "A345172", "A345192", "A345194" ]
[ "M1235", "N0472" ]
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001250.seq
46bde7458aff21dbfa3895f2b807d08e
A001251
Number of permutations of order n with the length of longest run equal to 3.
[ "0", "0", "2", "12", "70", "442", "3108", "24216", "208586", "1972904", "20373338", "228346522", "2763212980", "35926266244", "499676669254", "7405014187564", "116511984902094", "1940073930857802", "34087525861589564", "630296344519286304", "12235215845125112122", "248789737587365945992" ]
[ "nonn" ]
42
1
3
[ "A001250", "A001251", "A001252", "A001253", "A010026", "A211318" ]
[ "M2031", "N0803" ]
N. J. A. Sloane
2024-03-22T18:49:42
oeisdata/seq/A001/A001251.seq
86b8f3d37ce8b194d1b7d1bade916626
A001252
Number of permutations of order n with the length of longest run equal to 4.
[ "0", "0", "0", "2", "16", "134", "1164", "10982", "112354", "1245676", "14909340", "191916532", "2646100822", "38932850396", "609137502242", "10101955358506", "177053463254274", "3270694371428814", "63524155236581118", "1294248082658393546", "27604013493657933856", "615135860462018980316" ]
[ "nonn" ]
42
1
4
[ "A001250", "A001251", "A001252", "A001253", "A010026", "A211318" ]
[ "M2092", "N0827" ]
N. J. A. Sloane
2024-03-22T18:38:01
oeisdata/seq/A001/A001252.seq
25b046cc381fddcdd8016b055ba0cce8
A001253
Number of permutations of order n with the length of longest run equal to 5.
[ "0", "0", "0", "0", "2", "20", "198", "2048", "22468", "264538", "3340962", "45173518", "652209564", "10024669626", "163546399460", "2823941647390", "51468705947590", "987671243816650", "19909066390361346", "420650676776338140", "9297308938203169622", "214562999510569012168" ]
[ "nonn" ]
41
1
5
[ "A001250", "A001251", "A001252", "A001253", "A010026", "A211318" ]
[ "M2123", "N0840" ]
N. J. A. Sloane
2024-03-22T19:18:35
oeisdata/seq/A001/A001253.seq
08f2976fb14717f71bbc336ae97b952c
A001254
Squares of Lucas numbers.
[ "4", "1", "9", "16", "49", "121", "324", "841", "2209", "5776", "15129", "39601", "103684", "271441", "710649", "1860496", "4870849", "12752041", "33385284", "87403801", "228826129", "599074576", "1568397609", "4106118241", "10749957124", "28143753121", "73681302249", "192900153616", "505019158609", "1322157322201", "3461452808004", "9062201101801", "23725150497409" ]
[ "nonn", "easy" ]
96
0
1
[ "A000032", "A000204", "A001254", "A001638", "A005970", "A006499", "A007598", "A075150", "A079291", "A103324" ]
null
N. J. A. Sloane
2022-09-08T08:44:28
oeisdata/seq/A001/A001254.seq
e6fde27c7523bead97ce6395068fc6f8
A001255
Squares of partition numbers.
[ "1", "1", "4", "9", "25", "49", "121", "225", "484", "900", "1764", "3136", "5929", "10201", "18225", "30976", "53361", "88209", "148225", "240100", "393129", "627264", "1004004", "1575025", "2480625", "3833764", "5934096", "9060100", "13823524", "20839225", "31404816", "46812964", "69705801", "102880449", "151536100" ]
[ "nonn", "easy", "changed" ]
37
0
3
[ "A000041", "A000290", "A001255", "A054440", "A133042", "A200089", "A304990" ]
null
N. J. A. Sloane
2025-04-24T06:29:19
oeisdata/seq/A001/A001255.seq
b72dc5b681e8e7f2f8cc959efa04af70
A001256
Squares of numbers of trees.
[ "1", "1", "1", "1", "4", "9", "36", "121", "529", "2209", "11236", "55225", "303601", "1692601", "9979281", "59923081", "373262400", "2364779641", "15343033689", "101095382025", "677435994225", "4598901695025", "31626631547536", "219871778549476", "1544481904210609", "10948878748872100", "78284374662902500" ]
[ "nonn" ]
16
0
5
[ "A000055", "A001256" ]
null
N. J. A. Sloane
2022-02-02T00:08:45
oeisdata/seq/A001/A001256.seq
290bf2bc9ea2e561cd14f16c2203e5ef
A001257
Squares of numbers of rooted trees.
[ "1", "1", "4", "16", "81", "400", "2304", "13225", "81796", "516961", "3392964", "22714756", "155900196", "1087218729", "7710771721", "55404215161", "403030713409", "2962388303281", "21983682632976", "164512124707984", "1240577449436224" ]
[ "nonn" ]
11
0
3
[ "A000081", "A001257" ]
null
N. J. A. Sloane
2022-02-02T00:08:04
oeisdata/seq/A001/A001257.seq
a5268da0ef101b68556e866d92566d1b
A001258
Number of labeled n-node trees with unlabeled end-points.
[ "1", "1", "2", "6", "25", "135", "892", "6937", "61886", "621956", "6946471", "85302935", "1141820808", "16540534553", "257745010762", "4298050731298", "76356627952069", "1439506369337319", "28699241994332940", "603229325513240569", "13330768181611378558", "308967866671489907656", "7493481669479297191451", "189793402599733802743015", "5010686896406348299630712" ]
[ "nonn", "nice" ]
32
2
3
[ "A001258", "A151880" ]
[ "M1678", "N0660" ]
N. J. A. Sloane. More terms from N. J. A. Sloane, Jun 07 2012
2017-05-14T04:36:14
oeisdata/seq/A001/A001258.seq
d8d3f683046ecdc78492ff4029f0009e
A001259
A sequence of sorted odd primes 3 = p_1 < p_2 < ... < p_m such that p_i-2 divides the product p_1*p_2*...*p_(i-1) of the earlier primes and each prime factor of p_i-1 is a prime factor of twice the product.
[ "3", "5", "7", "17", "19", "37", "97", "113", "257", "401", "487", "631", "971", "1297", "1801", "19457", "22051", "28817", "65537", "157303", "160001" ]
[ "nonn", "fini", "full" ]
37
1
1
[ "A001259", "A007015", "A342701" ]
[ "M2423", "N0958" ]
N. J. A. Sloane
2021-03-19T06:58:30
oeisdata/seq/A001/A001259.seq
e63422691f71e33714487e50f8f07a57
A001260
Number of permutations of length n with 4 consecutive ascending pairs.
[ "0", "0", "0", "0", "1", "5", "45", "385", "3710", "38934", "444990", "5506710", "73422855", "1049946755", "16035550531", "260577696015", "4489954146860", "81781307674780", "1570201107355980", "31698434854748604", "671260973394676605", "14879618243581997745" ]
[ "nonn" ]
43
1
6
[ "A000166", "A000255", "A000274", "A000313", "A001260", "A001261", "A010027" ]
[ "M3999", "N1657" ]
N. J. A. Sloane
2020-05-09T15:11:53
oeisdata/seq/A001/A001260.seq
4fd220b9989b29a2c465621af2de4f40
A001261
Number of permutations of length n with 5 consecutive ascending pairs.
[ "0", "0", "0", "0", "0", "1", "6", "63", "616", "6678", "77868", "978978", "13216104", "190899423", "2939850914", "48106651593", "833848627248", "15265844099324", "294412707629208", "5966764207952724", "126793739418994416", "2819296088257641741", "65470320271760790078" ]
[ "nonn" ]
26
1
7
[ "A000166", "A000255", "A000274", "A000313", "A001260", "A001261", "A010027" ]
[ "M4273", "N1786" ]
N. J. A. Sloane
2021-12-19T09:53:57
oeisdata/seq/A001/A001261.seq
8fc7fd9064bca0e35e591ae0da13012b
A001262
Strong pseudoprimes to base 2.
[ "2047", "3277", "4033", "4681", "8321", "15841", "29341", "42799", "49141", "52633", "65281", "74665", "80581", "85489", "88357", "90751", "104653", "130561", "196093", "220729", "233017", "252601", "253241", "256999", "271951", "280601", "314821", "357761", "390937", "458989", "476971", "486737" ]
[ "nonn", "nice" ]
97
1
1
[ "A001262", "A001567", "A020229", "A020231", "A020233", "A056915", "A072276", "A074773", "A215568" ]
null
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001262.seq
595a00bbf09038ac0aab1964df7fd9c6
A001263
Triangle of Narayana numbers T(n,k) = C(n-1,k-1)*C(n,k-1)/k with 1 <= k <= n, read by rows. Also called the Catalan triangle.
[ "1", "1", "1", "1", "3", "1", "1", "6", "6", "1", "1", "10", "20", "10", "1", "1", "15", "50", "50", "15", "1", "1", "21", "105", "175", "105", "21", "1", "1", "28", "196", "490", "490", "196", "28", "1", "1", "36", "336", "1176", "1764", "1176", "336", "36", "1", "1", "45", "540", "2520", "5292", "5292", "2520", "540", "45", "1", "1", "55", "825", "4950", "13860", "19404", "13860", "4950", "825" ]
[ "nonn", "easy", "tabl", "nice", "look" ]
687
1
5
[ "A000081", "A000108", "A000217", "A000372", "A001263", "A002083", "A002378", "A002415", "A005043", "A006542", "A006857", "A007318", "A008459", "A010790", "A016098", "A032027", "A033282", "A055277", "A056932", "A056939", "A056940", "A056941", "A065329", "A073345", "A084938", "A089231", "A089732", "A090181", "A103371", "A105278", "A108679", "A119900", "A131198", "A132710", "A134264", "A135278", "A142465", "A142467", "A142468", "A145596", "A145597", "A145598", "A145599", "A145903", "A145904", "A174109", "A181143", "A181144", "A189232", "A243752", "A342889", "A342890", "A342891", "A358371" ]
null
N. J. A. Sloane
2025-03-19T17:42:33
oeisdata/seq/A001/A001263.seq
c98fb99a40a594365079ddc135376144
A001264
Final 2 digits of 4^n.
[ "1", "4", "16", "64", "56", "24", "96", "84", "36", "44", "76", "4", "16", "64", "56", "24", "96", "84", "36", "44", "76", "4", "16", "64", "56", "24", "96", "84", "36", "44", "76", "4", "16", "64", "56", "24", "96", "84", "36", "44", "76", "4", "16", "64", "56", "24", "96", "84", "36", "44", "76", "4", "16", "64", "56", "24", "96" ]
[ "nonn", "easy" ]
21
0
2
null
null
N. J. A. Sloane
2022-09-08T08:44:29
oeisdata/seq/A001/A001264.seq
071c3acbf0736cb3f4020b837a0b7823
A001265
Table T(n,k) in which n-th row lists prime factors of 2^n - 1 (n >= 2), with repetition.
[ "3", "7", "3", "5", "31", "3", "3", "7", "127", "3", "5", "17", "7", "73", "3", "11", "31", "23", "89", "3", "3", "5", "7", "13", "8191", "3", "43", "127", "7", "31", "151", "3", "5", "17", "257", "131071", "3", "3", "3", "7", "19", "73", "524287", "3", "5", "5", "11", "31", "41", "7", "7", "127", "337", "3", "23", "89", "683", "47", "178481", "3", "3", "5", "7", "13", "17", "241" ]
[ "nonn", "tabf" ]
51
2
1
[ "A001265", "A060443", "A182590" ]
null
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001265.seq
3457a69e57d22fa8944fddf592e9fba2
A001266
One-half the number of permutations of length n without rising or falling successions.
[ "0", "0", "1", "7", "45", "323", "2621", "23811", "239653", "2648395", "31889517", "415641779", "5830753109", "87601592187", "1403439027805", "23883728565283", "430284458893701", "8181419271349931", "163730286973255373", "3440164703027845395", "75718273707281368117", "1742211593431076483419" ]
[ "nonn", "changed" ]
44
2
4
[ "A001266", "A002464", "A010028", "A086856" ]
[ "M4426", "N1871" ]
N. J. A. Sloane
2025-04-25T17:10:24
oeisdata/seq/A001/A001266.seq
8a455749ae907341b3d71d16cb31aec6
A001267
One-half the number of permutations of length n with exactly 3 rising or falling successions.
[ "0", "0", "0", "0", "1", "8", "60", "444", "3599", "32484", "325322", "3582600", "43029621", "559774736", "7841128936", "117668021988", "1883347579515", "32026067455084", "576605574327174", "10957672400252944", "219190037987444577", "4603645435776504120", "101292568208941883236", "2329975164242735146316" ]
[ "nonn" ]
23
0
6
[ "A000130", "A001267", "A002464", "A010028", "A086852", "A086854" ]
[ "M4550", "N1934" ]
N. J. A. Sloane
2021-12-19T09:54:41
oeisdata/seq/A001/A001267.seq
82e42ae5eb1a1c3df93faa805bca5eb3
A001268
One-half the number of permutations of length n with exactly 4 rising or falling successions.
[ "0", "0", "0", "0", "0", "1", "11", "113", "1099", "11060", "118484", "1366134", "16970322", "226574211", "3240161105", "49453685911", "802790789101", "13815657556958", "251309386257874", "4818622686395380", "97145520138758844", "2054507019515346789", "45484006970415223287", "1052036480881734378541" ]
[ "nonn" ]
25
0
7
[ "A000130", "A001268", "A002464", "A010028", "A086852", "A086855" ]
[ "M4805", "N2053" ]
N. J. A. Sloane
2021-12-19T09:54:54
oeisdata/seq/A001/A001268.seq
2ddce77d699cd668980a9d3b2a7542b8
A001269
Table T(n,k) in which n-th row lists prime factors of 2^n + 1 (n >= 0), with repetition.
[ "2", "3", "5", "3", "3", "17", "3", "11", "5", "13", "3", "43", "257", "3", "3", "3", "19", "5", "5", "41", "3", "683", "17", "241", "3", "2731", "5", "29", "113", "3", "3", "11", "331", "65537", "3", "43691", "5", "13", "37", "109", "3", "174763", "17", "61681", "3", "3", "43", "5419", "5", "397", "2113", "3", "2796203", "97", "257", "673", "3", "11", "251", "4051" ]
[ "nonn", "tabf" ]
36
0
1
[ "A001269", "A054992", "A060444" ]
null
N. J. A. Sloane
2024-02-29T23:08:14
oeisdata/seq/A001/A001269.seq
947e8d976625679ec72809d113599e7e
A001270
Table of prime factors of 10^n - 1 (with multiplicity).
[ "3", "3", "3", "3", "11", "3", "3", "3", "37", "3", "3", "11", "101", "3", "3", "41", "271", "3", "3", "3", "7", "11", "13", "37", "3", "3", "239", "4649", "3", "3", "11", "73", "101", "137", "3", "3", "3", "3", "37", "333667", "3", "3", "11", "41", "271", "9091", "3", "3", "21649", "513239", "3", "3", "3", "7", "11", "13", "37", "101", "9901", "3", "3", "53", "79", "265371653" ]
[ "nonn", "tabf" ]
26
1
1
[ "A001270", "A002283" ]
null
N. J. A. Sloane
2023-05-23T22:59:24
oeisdata/seq/A001/A001270.seq
a630ac49a0509aa69ee45a28d9d6e143
A001271
Irregular table read by rows: row n lists prime factors of 10^n +1, with multiplicity.
[ "2", "11", "101", "7", "11", "13", "73", "137", "11", "9091", "101", "9901", "11", "909091", "17", "5882353", "7", "11", "13", "19", "52579", "101", "3541", "27961", "11", "11", "23", "4093", "8779", "73", "137", "99990001", "11", "859", "1058313049", "29", "101", "281", "121499449", "7", "11", "13", "211", "241", "2161", "9091", "353", "449", "641", "1409", "69857" ]
[ "nonn", "tabf" ]
41
0
1
[ "A001271", "A028416", "A057934", "A062397" ]
null
N. J. A. Sloane, revised Jul 13 2009
2023-09-15T04:22:34
oeisdata/seq/A001/A001271.seq
8903c08f2c5560667162faaaccd7a3de
A001272
Numbers k such that k! - (k-1)! + (k-2)! - (k-3)! + ... - (-1)^k*1! is prime.
[ "3", "4", "5", "6", "7", "8", "10", "15", "19", "41", "59", "61", "105", "160", "661", "2653", "3069", "3943", "4053", "4998", "8275", "9158", "11164", "43592", "59961" ]
[ "nonn", "hard", "more", "nice", "fini" ]
71
1
1
[ "A001272", "A002981", "A002982", "A005165", "A100289" ]
null
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001272.seq
d341568670a77961ad39ceb465b5c584
A001273
Smallest number that takes n steps to reach 1 under iteration of sum-of-squares-of-digits map (= smallest "happy number" of height n).
[ "1", "10", "13", "23", "19", "7", "356", "78999" ]
[ "nonn", "base" ]
39
0
2
[ "A001273", "A007770", "A018785", "A176762" ]
null
N. J. A. Sloane
2025-01-05T19:51:31
oeisdata/seq/A001/A001273.seq
7849438da6e60b4381471f02a15163fb
A001274
Numbers k such that phi(k) = phi(k+1).
[ "1", "3", "15", "104", "164", "194", "255", "495", "584", "975", "2204", "2625", "2834", "3255", "3705", "5186", "5187", "10604", "11715", "13365", "18315", "22935", "25545", "32864", "38804", "39524", "46215", "48704", "49215", "49335", "56864", "57584", "57645", "64004", "65535", "73124", "105524", "107864", "123824", "131144", "164175", "184635" ]
[ "nonn", "easy", "nice", "changed" ]
151
1
2
[ "A000010", "A001274", "A001494", "A003275", "A003276", "A007015", "A051953", "A179186", "A179187", "A179188", "A179189", "A179202", "A217139" ]
[ "M2999", "N1215" ]
N. J. A. Sloane
2025-04-19T19:36:44
oeisdata/seq/A001/A001274.seq
d3f69386da3b95c61fe2b2216ab2d22f
A001275
Smallest prime p such that the product of q/(q-1) over the primes from prime(n) to p is greater than 2.
[ "3", "7", "23", "61", "127", "199", "337", "479", "677", "937", "1193", "1511", "1871", "2267", "2707", "3251", "3769", "4349", "5009", "5711", "6451", "7321", "8231", "9173", "10151", "11197", "12343", "13487", "14779", "16097", "17599", "19087", "20563", "22109", "23761", "25469", "27259", "29123", "31081", "33029" ]
[ "nonn" ]
21
1
1
[ "A001275", "A001276" ]
[ "M4378", "N1842" ]
N. J. A. Sloane
2019-07-12T19:04:14
oeisdata/seq/A001/A001275.seq
d3a0f00ae1e31d34ecb497e40c6ffd36
A001276
Smallest k such that the product of q/(q-1) over the primes from prime(n) to prime(n+k-1) is greater than 2.
[ "2", "3", "7", "15", "27", "41", "62", "85", "115", "150", "186", "229", "274", "323", "380", "443", "509", "577", "653", "733", "818", "912", "1010", "1114", "1222", "1331", "1448", "1572", "1704", "1845", "1994", "2138", "2289", "2445", "2609", "2774", "2948", "3127", "3311", "3502", "3699", "3900", "4112", "4324", "4546", "4775", "5016", "5255", "5493" ]
[ "nonn" ]
34
1
1
[ "A001275", "A001276", "A005101", "A108227" ]
[ "M2650", "N1057" ]
N. J. A. Sloane
2021-04-14T11:07:05
oeisdata/seq/A001/A001276.seq
08f8cdd5c2eab9e447e9daa05bde8d7a
A001277
Number of permutations of length n by rises.
[ "1", "3", "12", "56", "321", "2175", "17008", "150504", "1485465", "16170035", "192384876", "2483177808", "34554278857", "515620794591", "8212685046336", "139062777326000", "2494364438359953", "47245095998005059", "942259727190907180", "19737566982241851720", "433234326593362631601", "9943659797649140568863" ]
[ "nonn" ]
23
2
2
[ "A001277", "A173184" ]
[ "M2928", "N1176" ]
N. J. A. Sloane
2022-07-01T06:40:58
oeisdata/seq/A001/A001277.seq
1a788bef3c3c571db53eb5009d1fd1d6
A001278
Number of permutations of length n by rises.
[ "1", "11", "87", "693", "5934", "55674", "572650", "6429470", "78366855", "1031378445", "14583751161", "220562730171", "3553474061452", "60765835154948", "1099353888345924", "20980355229808524", "421242574828254525", "8876636475162819615", "195887449298481357835", "4517865858233007694865", "108699311713253202373146", "2723633081926998772488606" ]
[ "nonn" ]
17
4
2
null
[ "M4799", "N2050" ]
N. J. A. Sloane
2022-07-01T06:46:07
oeisdata/seq/A001/A001278.seq
bea140b84d8a5e896969a6423f58901c
A001279
Number of permutations of length n by rises.
[ "3", "53", "680", "8064", "96370", "1200070", "15778800", "220047400", "3257228485", "51125192475", "849388162448", "14905775547488", "275697902983860", "5362979000259804", "109488815508733440", "2341353038132316240", "52346701837709016375", "1221458048752142672625", "29697803502485749344120", "751211166036942984639200" ]
[ "nonn" ]
16
6
1
null
[ "M3159", "N1279" ]
N. J. A. Sloane
2022-07-01T06:50:22
oeisdata/seq/A001/A001279.seq
0cddbe9d787d6a5674bb1672e7087e08
A001280
Number of permutations of length n by rises.
[ "11", "309", "5805", "95575", "1516785", "24206055", "396475975", "6733084365", "119143997490", "2201649739310", "42514526708766", "857750898213594", "18068801884373310", "397038791150060850", "9090755207499817170", "216635190303090215910" ]
[ "nonn" ]
16
8
1
null
[ "M4811", "N2058" ]
N. J. A. Sloane
2022-07-01T07:30:34
oeisdata/seq/A001/A001280.seq
a0bad1e0a1fe891ae1643a05ed1e13cb
A001281
Image of n under the map n->n/2 if n even, n->3n-1 if n odd.
[ "0", "2", "1", "8", "2", "14", "3", "20", "4", "26", "5", "32", "6", "38", "7", "44", "8", "50", "9", "56", "10", "62", "11", "68", "12", "74", "13", "80", "14", "86", "15", "92", "16", "98", "17", "104", "18", "110", "19", "116", "20", "122", "21", "128", "22", "134", "23", "140", "24", "146", "25", "152", "26", "158", "27", "164", "28", "170", "29", "176", "30", "182", "31", "188" ]
[ "nonn", "easy" ]
24
0
2
[ "A001281", "A006370", "A006577", "A037082", "A037084", "A039500", "A039505", "A135727", "A135730" ]
null
N. J. A. Sloane
2022-10-21T22:07:49
oeisdata/seq/A001/A001281.seq
353a639557a9d0ffb1330cb9e4692ad8
A001282
Number of permutations of length n by rises.
[ "17", "259", "2770", "27978", "294602", "3331790", "40682144", "535206440", "7557750635", "114101726625", "1834757172082", "31313852523634", "565434670633580", "10771030900532868", "215881317066455232", "4541623615098815280" ]
[ "nonn" ]
14
6
1
[ "A001282", "A010030" ]
[ "M5047", "N2181" ]
N. J. A. Sloane
2022-02-03T00:31:44
oeisdata/seq/A001/A001282.seq
eeda7c16414f4e1dc4425a6e82c75065
A001283
Triangle read by rows, in which row n consists of n(n+m) for m = 1 .. n-1.
[ "6", "12", "15", "20", "24", "28", "30", "35", "40", "45", "42", "48", "54", "60", "66", "56", "63", "70", "77", "84", "91", "72", "80", "88", "96", "104", "112", "120", "90", "99", "108", "117", "126", "135", "144", "153", "110", "120", "130", "140", "150", "160", "170", "180", "190", "132", "143", "154", "165", "176", "187", "198", "209", "220", "231", "156", "168", "180" ]
[ "nonn", "easy", "tabl" ]
24
2
1
[ "A001283", "A003991", "A033581", "A063929", "A063930", "A085788" ]
null
N. J. A. Sloane
2022-02-03T00:32:10
oeisdata/seq/A001/A001283.seq
f88c9eeaa817227e046e2747a031ded1
A001284
Numbers of form m*k with m+1 <= k <= 2m-1.
[ "6", "12", "15", "20", "24", "28", "30", "35", "40", "42", "45", "48", "54", "56", "60", "63", "66", "70", "72", "77", "80", "84", "88", "90", "91", "96", "99", "104", "108", "110", "112", "117", "120", "126", "130", "132", "135", "140", "143", "144", "150", "153", "154", "156", "160", "165", "168", "170", "176", "180", "182", "187", "190", "192", "195", "198", "204", "208", "209", "210", "216", "220", "221", "224", "228", "231" ]
[ "nonn", "easy" ]
23
1
1
[ "A001284", "A005279" ]
null
N. J. A. Sloane
2025-02-11T20:33:39
oeisdata/seq/A001/A001284.seq
af0fc2ca7858e30123e450567c3a2d8f
A001285
Thue-Morse sequence: let A_k denote the first 2^k terms; then A_0 = 1 and for k >= 0, A_{k+1} = A_k B_k, where B_k is obtained from A_k by interchanging 1's and 2's.
[ "1", "2", "2", "1", "2", "1", "1", "2", "2", "1", "1", "2", "1", "2", "2", "1", "2", "1", "1", "2", "1", "2", "2", "1", "1", "2", "2", "1", "2", "1", "1", "2", "2", "1", "1", "2", "1", "2", "2", "1", "1", "2", "2", "1", "2", "1", "1", "2", "1", "2", "2", "1", "2", "1", "1", "2", "2", "1", "1", "2", "1", "2", "2", "1", "2", "1", "1", "2", "1", "2", "2", "1", "1", "2", "2", "1", "2", "1", "1", "2", "1", "2", "2", "1", "2", "1", "1", "2", "2", "1", "1", "2", "1", "2", "2", "1", "1", "2", "2", "1", "2", "1" ]
[ "nonn", "easy", "core", "nice" ]
136
0
2
[ "A001285", "A003159", "A010059", "A010060", "A026430", "A026465", "A029885", "A161175", "A225186", "A230958" ]
[ "M0193", "N0071" ]
N. J. A. Sloane
2024-03-01T11:07:55
oeisdata/seq/A001/A001285.seq
a6e3bb9589f1b96e2c25c92132e4b708
A001286
Lah numbers: a(n) = (n-1)*n!/2.
[ "1", "6", "36", "240", "1800", "15120", "141120", "1451520", "16329600", "199584000", "2634508800", "37362124800", "566658892800", "9153720576000", "156920924160000", "2845499424768000", "54420176498688000", "1094805903679488000", "23112569077678080000", "510909421717094400000" ]
[ "nonn", "easy", "nice" ]
173
2
2
[ "A000110", "A000111", "A001113", "A001286", "A001620", "A001710", "A002868", "A008292", "A008297", "A019538", "A051683", "A052609", "A053495", "A060570", "A060608", "A060612", "A060638", "A062119", "A075181", "A091725", "A099285", "A111596", "A135218", "A213168", "A278677", "A278678", "A278679", "S1", "S2" ]
[ "M4225", "N1766" ]
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001286.seq
6267adbab7ae228043ad8458e58d367a
A001287
a(n) = binomial coefficient C(n,10).
[ "1", "11", "66", "286", "1001", "3003", "8008", "19448", "43758", "92378", "184756", "352716", "646646", "1144066", "1961256", "3268760", "5311735", "8436285", "13123110", "20030010", "30045015", "44352165", "64512240", "92561040", "131128140", "183579396", "254186856", "348330136", "472733756", "635745396" ]
[ "nonn", "easy" ]
95
10
2
[ "A001287", "A001787", "A110555", "A242091" ]
[ "M4794", "N2046" ]
N. J. A. Sloane
2025-01-07T10:52:41
oeisdata/seq/A001/A001287.seq
5f86178c3c89b3a1584f460582793f5a
A001288
a(n) = binomial(n,11).
[ "1", "12", "78", "364", "1365", "4368", "12376", "31824", "75582", "167960", "352716", "705432", "1352078", "2496144", "4457400", "7726160", "13037895", "21474180", "34597290", "54627300", "84672315", "129024480", "193536720", "286097760", "417225900", "600805296", "854992152", "1203322288", "1676056044" ]
[ "nonn", "easy" ]
74
11
2
[ "A001288", "A001787", "A110555", "A242091" ]
[ "M4850", "N2073" ]
N. J. A. Sloane
2025-02-21T22:43:39
oeisdata/seq/A001/A001288.seq
1dd485fa2b0f5e3fd67a3cbadde3a373
A001289
Number of equivalence classes of Boolean functions modulo linear functions.
[ "1", "2", "3", "8", "48", "150357", "63379147320777408548" ]
[ "nonn", "hard", "more", "nice" ]
16
1
2
[ "A001289", "A109003" ]
null
N. J. A. Sloane.
2018-02-11T03:06:17
oeisdata/seq/A001/A001289.seq
55b472f23374d6b759eed4a401410e1e
A001290
Order of "Restricted Affine Group" on n variables.
[ "192", "21504", "10321924" ]
[ "nonn", "more", "bref" ]
17
2
1
[ "A001290", "A143037" ]
null
N. J. A. Sloane
2022-02-03T00:32:23
oeisdata/seq/A001/A001290.seq
c062e8d44ff331772206d4b427e15c21
A001291
Number of conjugacy classes in Restricted Affine Group on n variables.
[ "13", "28", "62", "124" ]
[ "nonn", "more" ]
8
2
1
null
null
N. J. A. Sloane
2022-02-03T00:32:37
oeisdata/seq/A001/A001291.seq
ab6b30d5909fa061351255f4d006937c
A001292
Concatenations of cyclic permutations of initial positive integers.
[ "1", "12", "21", "123", "231", "312", "1234", "2341", "3412", "4123", "12345", "23451", "34512", "45123", "51234", "123456", "234561", "345612", "456123", "561234", "612345", "1234567", "2345671", "3456712", "4567123", "5671234", "6712345", "7123456" ]
[ "nonn", "base" ]
79
1
2
[ "A001292", "A093771", "A134804", "A352991" ]
null
R. Muller
2022-07-01T22:04:15
oeisdata/seq/A001/A001292.seq
be5bb97b6c924844065a2d2dd506fa1c
A001293
Leech triangle: k-th number (0 <= k <= n) in n-th row (0 <= n) is number of octads in S(5,8,24) containing k given points and missing n-k given points.
[ "759", "506", "253", "330", "176", "77", "210", "120", "56", "21", "130", "80", "40", "16", "5", "78", "52", "28", "12", "4", "1", "46", "32", "20", "8", "4", "0", "1", "30", "16", "16", "4", "4", "0", "0", "1", "30", "0", "16", "0", "4", "0", "0", "0", "1" ]
[ "nonn", "tabl", "fini", "full", "nice" ]
14
0
1
null
null
N. J. A. Sloane
2022-01-29T02:08:05
oeisdata/seq/A001/A001293.seq
072e6dfe049d0a75eaf8f3c87bb387fc
A001294
Triangle in which k-th number (0<=k<=n) in n-th row (0<=n) is number of dodecads in Golay code G_24 containing k given points and missing n-k given points.
[ "2576", "1288", "1288", "616", "672", "616", "280", "336", "336", "280", "120", "160", "176", "160", "120", "48", "72", "88", "88", "72", "48", "16", "32", "40", "48", "40", "32", "16", "0", "16", "16", "24", "24", "16", "16", "0", "0", "0", "16", "0", "24", "0", "16", "0", "0" ]
[ "nonn", "tabl", "fini", "full", "nice" ]
13
0
1
null
null
N. J. A. Sloane
2022-01-29T12:16:56
oeisdata/seq/A001/A001294.seq
0c53de616c4b3c0a19d406f68440c553
A001295
Triangle in which k-th number (0<=k<=n) in n-th row (0<=n) is number of hexads in S(5,6,12) containing k given points and missing n-k given points.
[ "132", "66", "66", "30", "36", "30", "12", "18", "18", "12", "4", "8", "10", "8", "4", "1", "3", "5", "5", "3", "1", "1", "0", "3", "2", "3", "0", "1" ]
[ "nonn", "tabl", "fini", "full" ]
11
0
1
null
null
N. J. A. Sloane
2022-02-03T00:32:52
oeisdata/seq/A001/A001295.seq
974326f9842a50911ab02016be77d296
A001296
4-dimensional pyramidal numbers: a(n) = (3*n+1)*binomial(n+2, 3)/4. Also Stirling2(n+2, n).
[ "0", "1", "7", "25", "65", "140", "266", "462", "750", "1155", "1705", "2431", "3367", "4550", "6020", "7820", "9996", "12597", "15675", "19285", "23485", "28336", "33902", "40250", "47450", "55575", "64701", "74907", "86275", "98890", "112840", "128216", "145112", "163625", "183855", "205905", "229881", "255892", "284050", "314470" ]
[ "nonn", "easy", "nice" ]
189
0
3
[ "A000217", "A000326", "A000914", "A001296", "A001297", "A001298", "A002411", "A008277", "A008517", "A034261", "A093560", "A094262", "A220212", "A241765", "A254142" ]
[ "M4385", "N1845" ]
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001296.seq
531664caa5ead7eb96a56b80bb04862c
A001297
Stirling numbers of the second kind S(n+3, n).
[ "0", "1", "15", "90", "350", "1050", "2646", "5880", "11880", "22275", "39325", "66066", "106470", "165620", "249900", "367200", "527136", "741285", "1023435", "1389850", "1859550", "2454606", "3200450", "4126200", "5265000", "6654375", "8336601", "10359090", "12774790", "15642600", "19027800" ]
[ "nonn", "easy" ]
106
0
3
[ "A001296", "A001297", "A001298", "A001303", "A008277", "A008517", "A048993", "A062196", "A094262" ]
[ "M4974", "N2136" ]
N. J. A. Sloane
2025-02-16T08:32:23
oeisdata/seq/A001/A001297.seq
f959054282bce581b57fd61f4bd8d402
A001298
Stirling numbers of the second kind S(n+4, n).
[ "0", "1", "31", "301", "1701", "6951", "22827", "63987", "159027", "359502", "752752", "1479478", "2757118", "4910178", "8408778", "13916778", "22350954", "34952799", "53374629", "79781779", "116972779", "168519505", "238929405", "333832005", "460192005", "626551380", "843303006", "1122998436", "1480692556" ]
[ "nonn", "easy" ]
86
0
3
[ "A000915", "A001296", "A001297", "A001298", "A008277", "A008517", "A094262" ]
[ "M5222", "N2272" ]
N. J. A. Sloane
2025-02-21T23:44:36
oeisdata/seq/A001/A001298.seq
95e000816043d7fc2e4848de73863072
A001299
Number of ways of making change for n cents using coins of 1, 5, 10, 25 cents.
[ "1", "1", "1", "1", "1", "2", "2", "2", "2", "2", "4", "4", "4", "4", "4", "6", "6", "6", "6", "6", "9", "9", "9", "9", "9", "13", "13", "13", "13", "13", "18", "18", "18", "18", "18", "24", "24", "24", "24", "24", "31", "31", "31", "31", "31", "39", "39", "39", "39", "39", "49", "49", "49", "49", "49", "60", "60", "60", "60", "60", "73", "73", "73", "73", "73", "87", "87", "87", "87", "87", "103", "103", "103", "103", "103" ]
[ "nonn", "easy" ]
54
0
6
[ "A000008", "A001299", "A001300", "A169718" ]
null
N. J. A. Sloane, Mar 15 1996
2017-04-18T07:02:34
oeisdata/seq/A001/A001299.seq
7971245db88ab6c62ee63d2833f4a14b
A001300
Number of ways of making change for n cents using coins of 1, 5, 10, 25, 50 cents.
[ "1", "1", "1", "1", "1", "2", "2", "2", "2", "2", "4", "4", "4", "4", "4", "6", "6", "6", "6", "6", "9", "9", "9", "9", "9", "13", "13", "13", "13", "13", "18", "18", "18", "18", "18", "24", "24", "24", "24", "24", "31", "31", "31", "31", "31", "39", "39", "39", "39", "39", "50", "50", "50", "50", "50", "62", "62", "62", "62", "62", "77", "77", "77" ]
[ "nonn", "easy" ]
40
0
6
[ "A000008", "A001299", "A001300", "A169718" ]
null
N. J. A. Sloane, Mar 15 1996
2017-04-18T07:02:35
oeisdata/seq/A001/A001300.seq
1af5aac3a5ea0eb15047cd3b3422e1b1