Datasets:
christopher
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oeis

Dataset card Data Studio Files
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1999-12-11 03:00:00
2025-04-25 01:21:50
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32
A002901
n^3 - floor( n/3 ).
[ "0", "1", "8", "26", "63", "124", "214", "341", "510", "726", "997", "1328", "1724", "2193", "2740", "3370", "4091", "4908", "5826", "6853", "7994", "9254", "10641", "12160", "13816", "15617", "17568", "19674", "21943", "24380", "26990", "29781", "32758", "35926", "39293" ]
[ "nonn", "easy" ]
19
0
5
null
null
ochavez(AT)spin.com.mx (Oscar Chavez)
2020-04-23T20:02:22
oeisdata/seq/A002/A002901.seq
1da9168ce376972dbe15941d3a2295f7
A002902
Number of n-step self-avoiding walks on a cubic lattice with a first step along the positive x, y, or z axis.
[ "3", "15", "75", "363", "1767", "8463", "40695", "193983", "926943", "4404939", "20967075", "99421371", "471987255", "2234455839", "10587573027", "50060937987", "236865126051", "1118861842047", "5288016609807", "24958663919367", "117855045251079", "555890991721203", "2622994107595707" ]
[ "nonn", "walk", "nice" ]
24
0
5
[ "A001411", "A001412", "A001413", "A002902", "A078717" ]
[ "M2990", "N1210" ]
N. J. A. Sloane
2022-01-31T01:10:02
oeisdata/seq/A002/A002902.seq
2a8daebed5581a4116252bc4a2cf8d50
A002903
Number of n-step self-avoiding walks on b.c.c. lattice (version 1).
[ "1", "4", "28", "196", "1324", "8980", "60028", "402412", "2675860", "17826340", "118145548", "784024780", "5184334996", "34313323804", "226516271020", "1496391824212", "9865667928796", "65080520041804", "428641139406628", "2824446024265444", "18587519784608836", "122369125319060884" ]
[ "nonn", "walk" ]
39
0
5
[ "A001666", "A002903" ]
[ "M3624", "N1472" ]
N. J. A. Sloane
2022-10-17T01:56:16
oeisdata/seq/A002/A002903.seq
37520067b65d198381ced601af67f567
A002904
Delete all letters except c, d, i, l, m, v, x from the US English name of n, then read as Roman numeral if possible, otherwise 0.
[ "0", "0", "0", "0", "4", "9", "5", "1", "1", "0", "55", "55", "1", "0", "1", "9", "5", "1", "1", "0", "0", "0", "0", "0", "4", "9", "5", "1", "1", "1", "1", "1", "1", "1", "0", "0", "4", "2", "2", "0", "0", "0", "0", "0", "4", "9", "5", "1", "1", "1", "1", "1", "1", "1", "0", "0", "4", "2", "2", "9", "9", "9", "9", "9", "0", "0", "0", "0", "0", "5", "5", "5", "5", "5", "0", "0", "0", "6", "6", "1", "1", "1", "1", "1", "0", "0", "4", "2", "2", "1", "1", "1", "1", "1", "0", "0", "4", "2", "2", "0" ]
[ "nonn", "word" ]
42
0
5
[ "A002904", "A092302", "A121305" ]
null
J. H. Conway
2024-11-10T23:04:06
oeisdata/seq/A002/A002904.seq
035634bdb649f2dd9042b74690b51c9a
A002905
Number of connected graphs with n edges.
[ "1", "1", "1", "3", "5", "12", "30", "79", "227", "710", "2322", "8071", "29503", "112822", "450141", "1867871", "8037472", "35787667", "164551477", "779945969", "3804967442", "19079312775", "98211456209", "518397621443", "2802993986619", "15510781288250", "87765472487659", "507395402140211", "2994893000122118", "18035546081743772", "110741792670074054", "692894304050453139" ]
[ "nonn", "nice" ]
66
0
5
[ "A000664", "A002905", "A003089", "A046091", "A054923", "A054924", "A275421" ]
[ "M2486", "N0985" ]
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002905.seq
1c074295ce28f4f72cd986851896b588
A002906
High temperature series for spin-1/2 Ising magnetic susceptibility on 2D square lattice.
[ "1", "4", "12", "36", "100", "276", "740", "1972", "5172", "13492", "34876", "89764", "229628", "585508", "1486308", "3763460", "9497380", "23918708", "60080156", "150660388", "377009364", "942106116", "2350157268", "5855734740", "14569318492", "36212402548", "89896870204" ]
[ "nonn", "nice" ]
57
0
5
[ "A002906", "A002908", "A002910", "A002913", "A002920", "A002927", "A005401" ]
[ "M3447", "N1401" ]
N. J. A. Sloane
2024-05-04T05:13:01
oeisdata/seq/A002/A002906.seq
05b8b38031ef90e80b57dddc8930c56f
A002907
High temperature series in v = tanh(J/kT) for residual correlation function (correction to susceptibility) for the spin-1/2 Ising model on square lattice.
[ "2", "2", "20", "38", "146", "368", "1070", "2824", "7680", "19996", "53024", "136350", "355254", "906254", "2331416", "5909810", "15067236", "37992680", "96210436", "241564514", "608469654", "1522388638", "3818281784", "9525139886", "23806217352", "59237754234", "147621207142", "366533832540", "911151508282" ]
[ "nonn" ]
19
0
5
[ "A002906", "A002907", "A002908" ]
[ "M0391", "N0149" ]
N. J. A. Sloane
2021-03-01T07:21:03
oeisdata/seq/A002/A002907.seq
cf1ec688f2523c36234af38e4f286a31
A002908
High temperature expansion of -u/J in odd powers of v = tanh(J/kT), where u is energy per site of the spin-1/2 Ising model on square lattice with nearest-neighbor interaction J at temperature T.
[ "2", "4", "8", "24", "84", "328", "1372", "6024", "27412", "128228", "613160", "2985116", "14751592", "73825416", "373488764", "1907334616", "9820757380", "50934592820", "265877371160", "1395907472968", "7366966846564", "39062802311672", "208015460898924", "1112050252939612", "5966352507546872" ]
[ "nonn", "nice" ]
34
0
5
[ "A002906", "A002908", "A002930", "A010571", "A010572", "A010573", "A010574" ]
[ "M1161", "N0444" ]
N. J. A. Sloane, Simon Plouffe
2024-04-27T15:53:35
oeisdata/seq/A002/A002908.seq
5ef2ef017a6209806635b3f8210d19de
A002909
Low temperature energy function for square lattice.
[ "2", "0", "-8", "-24", "-72", "-240", "-896", "-3640", "-15688", "-70512", "-326968", "-1553288", "-7523520", "-37026704", "-184677536", "-931655064", "-4746324296", "-24387839056", "-126257024696", "-658011767016", "-3449826712952", "-18183760406080", "-96309365029424", "-512340286827272" ]
[ "sign" ]
29
0
5
null
[ "M0035", "N0009" ]
N. J. A. Sloane
2020-11-29T02:34:13
oeisdata/seq/A002/A002909.seq
cbc91b274c34bef461f76f20ea15be6e
A002910
High-temperature series in v = tanh(J/kT) for susceptibility for the Ising model on honeycomb structure.
[ "1", "3", "6", "12", "24", "48", "90", "168", "318", "600", "1098", "2004", "3696", "6792", "12270", "22140", "40224", "72888", "130650", "234012", "421176", "756624", "1348998", "2403840", "4299018", "7677840", "13635630", "24206220", "43092888", "76635984", "135698970", "240199320", "426144654", "755420328", "1334488074" ]
[ "nonn", "nice" ]
21
0
5
[ "A002910", "A002978" ]
[ "M2558", "N1012" ]
N. J. A. Sloane
2021-03-03T09:02:48
oeisdata/seq/A002/A002910.seq
6157ce47941f8967c5871c5d508f105a
A002911
Erroneous version of A047709.
[ "0", "0", "1", "0", "12", "4", "129", "122", "1332", "960", "10919", "11372", "132900", "126396", "1299851", "1349784" ]
[ "dead" ]
37
0
5
null
[ "M4819" ]
null
2021-03-03T04:17:36
oeisdata/seq/A002/A002911.seq
cbcb5f33b18841edfdde94c481ce1bbc
A002912
Low-temperature series in z = exp(-2J/kT) for ferromagnetic susceptibility for the Ising model on honeycomb structure.
[ "0", "0", "1", "6", "27", "122", "516", "2148", "8792", "35622", "143079", "570830", "2264649", "8942436", "35169616", "137839308", "538594704", "2098892928", "8159937669", "31656305550", "122575164923", "473797120338", "1828512928200", "7046581314292", "27119735418924", "104247226432566", "400272672674603" ]
[ "nonn" ]
28
0
5
[ "A002912", "A002978" ]
[ "M4179", "N1740" ]
N. J. A. Sloane
2021-03-03T09:37:41
oeisdata/seq/A002/A002912.seq
4507da502d3968dcf46bae5fd24ea822
A002913
High temperature series for spin-1/2 Ising magnetic susceptibility on 3-dimensional simple cubic lattice.
[ "1", "6", "30", "150", "726", "3510", "16710", "79494", "375174", "1769686", "8306862", "38975286", "182265822", "852063558", "3973784886", "18527532310", "86228667894", "401225368086", "1864308847838", "8660961643254", "40190947325670", "186475398518726", "864404776466406", "4006394107568934", "18554916271112254", "85923704942057238" ]
[ "nonn", "nice" ]
84
0
5
[ "A001393", "A002170", "A002906", "A002910", "A002913", "A002914", "A002915", "A002916", "A002920", "A002921", "A002926", "A003119", "A003279", "A003490", "A007287", "A010040", "A010043", "A010046", "A010556", "A010571", "A010579", "A010580", "A030008" ]
[ "M4201", "N1753" ]
N. J. A. Sloane
2023-10-09T10:10:14
oeisdata/seq/A002/A002913.seq
aabe37d293ca616a2108ec0c3997c95e
A002914
Susceptibility series for b.c.c. lattice.
[ "1", "8", "56", "392", "2648", "17864", "118760", "789032", "5201048", "34268104", "224679864", "1472595144", "9619740648", "62823141192", "409297617672", "2665987056200", "17333875251192", "112680746646856", "731466943653464", "4747546469665832", "30779106675700312", "199518218638233896", "1292141318087690824", "8367300424426139624", "54141252229349325768", "350288350314921653160" ]
[ "nonn", "nice" ]
33
0
5
null
[ "M4544", "N1928" ]
N. J. A. Sloane
2022-02-09T20:18:46
oeisdata/seq/A002/A002914.seq
3fd21008d79f4031476de1f8bd1ef37e
A002915
Low temperature series for spin-1/2 Ising antiferromagnetic susceptibility for 3-dimensional simple cubic lattice.
[ "0", "0", "4", "0", "0", "-8", "60", "-144", "416", "-1248", "4200", "-13248", "42936", "-138072", "452840", "-1480944", "4883688", "-16114784", "53457696", "-177637248" ]
[ "sign", "nice", "more" ]
27
0
5
[ "A002915", "A002926", "A002979", "A007216", "A007217", "A007218" ]
[ "M3187", "N1290" ]
N. J. A. Sloane
2022-02-22T00:28:54
oeisdata/seq/A002/A002915.seq
e91bea736a09d87ac8b7142a5cebf500
A002916
High temperature series for spin-1/2 Ising specific heat on 3-dimensional simple cubic lattice.
[ "3", "33", "564", "8976", "155124", "2791308", "51382068", "962178084", "18258531348", "350143322088", "6772382631732", "131922552534036", "2585198190891636", "50919899448451512", "1007393565758096820", "20007153991627682124", "398699967207692643924", "7969220499183448073760", "159718349893920279061428" ]
[ "nonn" ]
41
0
5
[ "A001393", "A001408", "A002169", "A002913", "A002916", "A002917", "A002918", "A010571", "A029872" ]
[ "M3133", "N1271" ]
N. J. A. Sloane
2022-02-15T13:58:32
oeisdata/seq/A002/A002916.seq
69c6f51818b252fe7f352c73a598da14
A002917
High temperature series for spin-1/2 Ising specific heat on 3-dimensional b.c.c. lattice.
[ "4", "140", "4056", "129360", "4381848", "153700408", "5519859080", "201714989064" ]
[ "nonn", "more" ]
33
0
5
[ "A001406", "A002167", "A002914", "A002916", "A002917", "A002918", "A047711" ]
[ "M3718", "N1520" ]
N. J. A. Sloane
2022-02-15T13:57:12
oeisdata/seq/A002/A002917.seq
eb4f2ce54f6f0c77e997b61c8586fbc0
A002918
High temperature series for spin-1/2 Ising specific heat on 3-dimensional f.c.c. lattice.
[ "6", "48", "390", "3216", "26844", "229584", "2006736", "17809008", "159799812", "1446245424", "13181330772", "120849559824", "1113598633188" ]
[ "nonn", "more" ]
30
0
5
[ "A001407", "A002165", "A002916", "A002917", "A002918", "A002921" ]
[ "M4255", "N1777" ]
N. J. A. Sloane
2022-02-15T11:40:34
oeisdata/seq/A002/A002918.seq
d48aed8a405c43365085f84ea05364df
A002919
High-temperature series for susceptibility for the spin-1/2 Ising model on hexagonal lattice.
[ "1", "6", "24", "90", "318", "1098", "3696", "12270", "40224", "130650", "421176", "1348998", "4299018", "13635630", "43092888", "135698970", "426144654", "1334488074", "4170038328", "13001153910", "40464412482", "125706293478", "389962873920", "1207855307874", "3736709089176", "11544946664622", "35633199126576" ]
[ "nonn", "nice" ]
19
0
5
[ "A002910", "A002919", "A002920", "A047709" ]
[ "M4162", "N1730" ]
N. J. A. Sloane
2021-03-03T06:45:36
oeisdata/seq/A002/A002919.seq
32d78572582d1070e6147e2e02f8ff2e
A002920
High-temperature series in w = tanh(J/kT) for ferromagnetic susceptibility for the spin-1/2 Ising model on hexagonal lattice.
[ "1", "6", "30", "138", "606", "2586", "10818", "44574", "181542", "732678", "2935218", "11687202", "46296210", "182588850", "717395262", "2809372302", "10969820358", "42724062966", "166015496838", "643768299018", "2491738141314", "9628130289018", "37146098272266", "143110933254702", "550643544948090" ]
[ "nonn", "nice" ]
32
0
5
[ "A002910", "A002919", "A002920", "A047709", "A128834" ]
[ "M4196", "N1750" ]
N. J. A. Sloane
2022-02-11T08:41:06
oeisdata/seq/A002/A002920.seq
3efd0476a74f84862407010c59ff3172
A002921
Susceptibility series for f.c.c. lattice.
[ "1", "12", "132", "1404", "14652", "151116", "1546332", "15734460", "159425580", "1609987708", "16215457188", "162961837500", "1634743178420", "16373484437340", "163778159931180", "1636328839130860" ]
[ "nonn", "nice" ]
34
0
5
[ "A002165", "A002166", "A002168", "A002170", "A002913", "A002914", "A002918", "A002921" ]
[ "M4866", "N2081" ]
N. J. A. Sloane
2023-01-13T17:12:23
oeisdata/seq/A002/A002921.seq
8414a0a48142dd90ed4890319515c905
A002922
Specific heat for diamond.
[ "0", "6", "-12", "-156", "1680", "21264", "-592032", "-5349216", "381679872", "1095380736", "-384803443200", "2445989918208", "547003852781568" ]
[ "sign", "more" ]
30
0
5
[ "A002165", "A002167", "A002169", "A002922", "A002923" ]
[ "M4103", "N1702" ]
N. J. A. Sloane
2022-06-18T08:42:34
oeisdata/seq/A002/A002922.seq
43af7bd42ec328dfba4b35869097f8e3
A002923
Susceptibility series for diamond.
[ "4", "16", "64", "736", "11584", "43072", "-607232", "50435584", "1204185088", "-38340475904", "-563767881728", "73927460466688", "311178505633792", "-151984023599341568" ]
[ "sign", "more" ]
15
0
5
null
[ "M3520", "N1429" ]
N. J. A. Sloane
2021-10-21T01:07:56
oeisdata/seq/A002/A002923.seq
a5c40037d3c876c978728cc1215579ea
A002924
Ferromagnetic susceptibility series for f.c.c. lattice.
[ "0", "0", "0", "0", "0", "0", "1", "0", "0", "0", "0", "24", "-26", "0", "0", "72", "378", "-1080", "665", "384", "1968", "2016", "-25698", "39552", "-3872", "20880", "-65727", "-379072", "1277646", "-986856", "176978", "-2163504", "-1818996", "27871080", "-47138844", "20789424", "-36509652", "77055330", "393046656", "-1402934816", "1403843388" ]
[ "sign" ]
29
0
5
[ "A002892", "A002921", "A002924", "A002925", "A002926", "A003196" ]
[ "M5141", "N2230" ]
N. J. A. Sloane
2022-02-16T07:41:47
oeisdata/seq/A002/A002924.seq
a2c176025952f507dcad436d85ed5a6e
A002925
Susceptibility series for b.c.c. lattice.
[ "0", "0", "0", "1", "0", "0", "16", "-18", "0", "252", "-576", "519", "3264", "-12468", "20568", "26662", "-215568", "528576", "-164616", "-3014889", "10894920", "-13796840", "-29909616", "190423962", "-399739840", "-22768752", "2803402560", "-8743064909" ]
[ "sign", "nice", "more" ]
33
0
5
[ "A002924", "A002925", "A002926", "A371049" ]
[ "M4997", "N2151" ]
N. J. A. Sloane
2024-03-11T12:57:28
oeisdata/seq/A002/A002925.seq
d88bd1d2995c3a7afa76cfbf0e41d596
A002926
Low temperature series for spin-1/2 Ising magnetic susceptibility on 3-dimensional simple cubic lattice.
[ "0", "0", "1", "0", "12", "-14", "135", "-276", "1520", "-4056", "17778", "-54392", "213522", "-700362", "2601674", "-8836812", "31925046", "-110323056", "393008712", "-1369533048", "4844047090", "-16947396000", "59723296431", "-209328634116", "736260986208", "-2582605180212", "9074182912884" ]
[ "sign", "nice" ]
36
0
5
null
[ "M4823", "N2064" ]
N. J. A. Sloane
2022-02-09T20:18:57
oeisdata/seq/A002/A002926.seq
fa8a0eed4dd9c8667d0c526523b27987
A002927
Low temperature series for spin-1/2 Ising magnetic susceptibility on 2D square lattice.
[ "0", "0", "1", "8", "60", "416", "2791", "18296", "118016", "752008", "4746341", "29727472", "185016612", "1145415208", "7059265827", "43338407712", "265168691392", "1617656173824", "9842665771649", "59748291677832", "361933688520940", "2188328005246304", "13208464812265559", "79600379336505560", "479025509574159232" ]
[ "nonn" ]
45
0
5
[ "A002890", "A002906", "A002912", "A002926", "A002927", "A002928", "A002979", "A010115", "A029872", "A047709" ]
[ "M4549", "N1933" ]
N. J. A. Sloane, Simon Plouffe
2024-05-06T12:56:33
oeisdata/seq/A002/A002927.seq
15ddf439cfdac1359babfae10d0335f4
A002928
Magnetization for square lattice.
[ "1", "0", "-2", "-8", "-34", "-152", "-714", "-3472", "-17318", "-88048", "-454378", "-2373048", "-12515634", "-66551016", "-356345666", "-1919453984", "-10392792766", "-56527200992", "-308691183938", "-1691769619240", "-9301374102034" ]
[ "sign", "easy" ]
28
0
5
[ "A002927", "A002928", "A002929", "A002930", "A003193", "A003196", "A007206", "A007207", "A010102", "A010103", "A010104", "A010105", "A010106", "A030120", "A030121", "A057374", "A057378" ]
[ "M1853", "N0733" ]
N. J. A. Sloane, Simon Plouffe
2024-04-27T14:26:18
oeisdata/seq/A002/A002928.seq
186b30f46389eafdeea89b9bbc0ea6fe
A002929
Magnetization for cubic lattice.
[ "1", "0", "0", "-2", "0", "-12", "14", "-90", "192", "-792", "2148", "-7716", "23262", "-79512", "252054", "-846628", "2753520", "-9205800", "30371124", "-101585544", "338095596", "-1133491188", "3794908752", "-12758932158", "42903505030", "-144655483440", "488092130664", "-1650000819068", "5583090702798", "-18918470423736", "64167341172984", "-217893807812346", "740578734923544" ]
[ "sign", "nice" ]
21
0
5
null
[ "M0038", "N0011" ]
N. J. A. Sloane
2021-10-21T01:08:16
oeisdata/seq/A002/A002929.seq
133d4fa68ab8e9af5df8fc8761e99d3a
A002930
Magnetization series for diamond.
[ "1", "0", "-2", "-8", "-26", "-80", "-268", "-944", "-3474", "-13072", "-49672", "-191272", "-744500", "-2924680", "-11596284", "-46364456" ]
[ "sign", "nice" ]
17
0
5
null
[ "M1844", "N0730" ]
N. J. A. Sloane, Simon Plouffe
2017-11-16T15:33:42
oeisdata/seq/A002/A002930.seq
492aeb9a1cc35e9031662f97ad42abd2
A002931
Number of self-avoiding polygons of length 2n on square lattice (not allowing rotations).
[ "0", "1", "2", "7", "28", "124", "588", "2938", "15268", "81826", "449572", "2521270", "14385376", "83290424", "488384528", "2895432660", "17332874364", "104653427012", "636737003384", "3900770002646", "24045500114388", "149059814328236", "928782423033008", "5814401613289290", "36556766640745936" ]
[ "nonn", "walk", "nice" ]
69
0
5
[ "A002931", "A010566", "A036638", "A036639", "A056634", "A057730", "A302335", "A302336" ]
[ "M1780", "N0703" ]
N. J. A. Sloane
2021-03-18T23:08:21
oeisdata/seq/A002/A002931.seq
5e8249de2fe0d5277d5d1ce137a0fa25
A002932
Erroneous version of A173380.
[ "1", "4", "12", "28", "68", "164", "396", "940", "2244", "5324", "12668", "29940", "71012", "167468", "396204" ]
[ "dead" ]
14
0
5
null
[ "M3437", "N1394" ]
null
2010-11-22T19:34:32
oeisdata/seq/A002/A002932.seq
55b1ef0d4fbf91787df1644b5aede4e6
A002933
Erroneous version of A174313.
[ "1", "6", "18", "54", "162", "474", "1398", "4074", "11898", "34554", "100302", "290334", "839466" ]
[ "dead" ]
17
0
5
null
[ "M4123", "N1711" ]
null
2010-11-27T14:00:43
oeisdata/seq/A002/A002933.seq
c9b1c2905f5293c5deb00169c3cacc56
A002934
Erroneous version of A174319.
[ "1", "6", "30", "126", "534", "2214", "9246", "38142", "157974", "649086", "2674926" ]
[ "dead" ]
13
0
5
null
[ "M4194", "N1749" ]
null
2010-11-27T14:01:25
oeisdata/seq/A002/A002934.seq
43f9b16d18cd01a2b3565d5a70ec6fe4
A002935
Number of series-reduced star graphs with n edges.
[ "1", "1", "2", "5", "9", "22", "62", "177", "560", "1939", "7067", "27331", "110871", "468684", "2057161", "9341736" ]
[ "nonn", "nice", "more" ]
21
0
5
[ "A002935", "A046752", "A360879" ]
[ "M1364", "N0528" ]
N. J. A. Sloane
2023-03-03T16:25:39
oeisdata/seq/A002/A002935.seq
d864ddaa15363824d28044d62c96303b
A002936
Solid partitions of n, distinct along rows.
[ "1", "3", "7", "16", "33", "71", "141", "284", "552", "1067", "2020", "3803", "7043", "12957", "23566", "42536", "76068", "135093", "238001", "416591" ]
[ "nonn" ]
11
0
5
null
[ "M2658", "N1061" ]
N. J. A. Sloane
2023-10-20T21:34:03
oeisdata/seq/A002/A002936.seq
98e73a2156cf63158c6fd372b2f554dd
A002937
An exotic continued fraction (for the real root of x^3 - 8*x - 10).
[ "3", "3", "7", "4", "2", "30", "1", "8", "3", "1", "1", "1", "9", "2", "2", "1", "3", "22986", "2", "1", "32", "8", "2", "1", "8", "55", "1", "5", "2", "28", "1", "5", "1", "1501790", "1", "2", "1", "7", "6", "1", "1", "5", "2", "1", "6", "2", "2", "1", "2", "1", "1", "3", "1", "3", "1", "2", "4", "3", "1", "35657" ]
[ "cofr", "nonn" ]
36
0
5
[ "A002937", "A160332" ]
[ "M2284", "N0903" ]
N. J. A. Sloane
2023-10-21T09:50:39
oeisdata/seq/A002/A002937.seq
b68ca830de9a8af124d7bdce8911ae1e
A002938
The minimal sequence from solving n^3 - m^2 = a(n).
[ "0", "1", "2", "0", "4", "9", "18", "17", "0", "24", "35", "36", "12", "40", "11", "0", "13", "56", "30", "79", "45", "39", "67", "100", "0", "113", "83", "48", "53", "104", "138", "7", "163", "100", "26", "0", "28", "116", "217", "9", "248", "104", "17", "80", "79", "8", "139", "297", "0", "316", "155", "17", "119", "145", "89", "55", "293", "252", "170", "225", "405", "184", "47", "0", "49" ]
[ "nonn" ]
38
0
5
[ "A002938", "A077119" ]
[ "M0033", "N0008" ]
N. J. A. Sloane
2023-10-21T06:34:41
oeisdata/seq/A002/A002938.seq
0cf9009eefe48a7e5770f40ad0afc591
A002939
a(n) = 2*n*(2*n-1).
[ "0", "2", "12", "30", "56", "90", "132", "182", "240", "306", "380", "462", "552", "650", "756", "870", "992", "1122", "1260", "1406", "1560", "1722", "1892", "2070", "2256", "2450", "2652", "2862", "3080", "3306", "3540", "3782", "4032", "4290", "4556", "4830", "5112", "5402", "5700", "6006", "6320", "6642", "6972", "7310", "7656", "8010", "8372" ]
[ "nonn", "nice", "easy" ]
205
0
5
[ "A000217", "A000290", "A000384", "A001107", "A002061", "A002378", "A002620", "A002939", "A002943", "A007742", "A010050", "A014105", "A016742", "A016754", "A016789", "A017041", "A017089", "A017485", "A033951", "A033953", "A033954", "A033988", "A033989", "A033991", "A033996", "A035608", "A053755", "A054552", "A054554", "A054556", "A054567", "A054569", "A080335", "A125202", "A137932", "A156859", "A226488", "A267682", "A268684", "A317186", "A371064" ]
null
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002939.seq
41b9a9e97b250a3272b00246b1c93e58
A002940
Arrays of dumbbells.
[ "1", "4", "11", "26", "56", "114", "223", "424", "789", "1444", "2608", "4660", "8253", "14508", "25343", "44030", "76136", "131110", "224955", "384720", "656041", "1115784", "1893216", "3205416", "5416441", "9136084", "15384563", "25866914", "43429784", "72821274", "121953943", "204002680", "340886973", "569047468", "949022608" ]
[ "nonn", "easy" ]
68
0
5
[ "A000045", "A001925", "A002889", "A002940", "A002941", "A006478", "A023610", "A046741", "A054454", "A055608", "A062123", "A062124", "A062125", "A062126", "A062127", "A067331", "A178523" ]
[ "M3415", "N1381" ]
N. J. A. Sloane
2025-01-05T19:51:32
oeisdata/seq/A002/A002940.seq
4035c26f9a5731645e35172c4ce3a1d2
A002941
Arrays of dumbbells.
[ "1", "7", "29", "94", "263", "667", "1577", "3538", "7622", "15900", "32314", "64274", "125561", "241569", "458715", "861242", "1601081", "2950693", "5396209", "9801012", "17692092", "31759800", "56727588", "100861716", "178585489", "314995915", "553650761", "969967510", "1694235803" ]
[ "nonn", "easy" ]
34
0
5
[ "A002889", "A002940", "A002941", "A046741", "A055608", "A062123", "A062127" ]
[ "M4396", "N1852" ]
N. J. A. Sloane
2022-09-08T08:44:31
oeisdata/seq/A002/A002941.seq
b4c3cf2014b30653e5c9698ce123a8ed
A002942
a(n) = n^2 written backwards.
[ "1", "4", "9", "61", "52", "63", "94", "46", "18", "1", "121", "441", "961", "691", "522", "652", "982", "423", "163", "4", "144", "484", "925", "675", "526", "676", "927", "487", "148", "9", "169", "4201", "9801", "6511", "5221", "6921", "9631", "4441", "1251", "61", "1861", "4671", "9481", "6391", "5202", "6112", "9022", "4032", "1042", "52", "1062" ]
[ "nonn", "base", "easy", "look" ]
54
0
5
[ "A000290", "A002942", "A004086", "A080334" ]
[ "M3370", "N1357" ]
N. J. A. Sloane
2023-12-28T07:07:53
oeisdata/seq/A002/A002942.seq
0cca05e6f397f6d666f2a65657f3e643
A002943
a(n) = 2*n*(2*n+1).
[ "0", "6", "20", "42", "72", "110", "156", "210", "272", "342", "420", "506", "600", "702", "812", "930", "1056", "1190", "1332", "1482", "1640", "1806", "1980", "2162", "2352", "2550", "2756", "2970", "3192", "3422", "3660", "3906", "4160", "4422", "4692", "4970", "5256", "5550", "5852", "6162", "6480", "6806", "7140", "7482", "7832", "8190", "8556", "8930" ]
[ "nonn", "easy", "nice" ]
127
0
5
[ "A000217", "A000290", "A000384", "A001107", "A001477", "A002061", "A002378", "A002620", "A002939", "A002943", "A003154", "A007395", "A007494", "A007742", "A014105", "A016742", "A016754", "A016813", "A033951", "A033952", "A033953", "A033954", "A033988", "A033989", "A033990", "A033991", "A033996", "A035608", "A045896", "A046092", "A053755", "A054000", "A054552", "A054554", "A054556", "A054567", "A054569", "A056220", "A080335", "A118729", "A137932", "A156859", "A173511", "A267682", "A317186" ]
null
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002943.seq
f6444a7fa6742fce1074851cdc91926e
A002944
a(n) = LCM(1,2,...,n) / n.
[ "1", "1", "2", "3", "12", "10", "60", "105", "280", "252", "2520", "2310", "27720", "25740", "24024", "45045", "720720", "680680", "12252240", "11639628", "11085360", "10581480", "232792560", "223092870", "1070845776", "1029659400", "2974571600", "2868336900", "80313433200", "77636318760", "2329089562800" ]
[ "nonn", "easy" ]
79
0
5
[ "A001142", "A001405", "A002944", "A003418", "A025527", "A025537", "A056606", "A100561" ]
[ "M0912", "N0344" ]
N. J. A. Sloane
2023-12-25T20:48:15
oeisdata/seq/A002/A002944.seq
95de35c98bf5b19d09c6f622b1f9f723
A002945
Continued fraction for cube root of 2.
[ "1", "3", "1", "5", "1", "1", "4", "1", "1", "8", "1", "14", "1", "10", "2", "1", "4", "12", "2", "3", "2", "1", "3", "4", "1", "1", "2", "14", "3", "12", "1", "15", "3", "1", "4", "534", "1", "1", "5", "1", "1", "121", "1", "2", "2", "4", "10", "3", "2", "2", "41", "1", "1", "1", "3", "7", "2", "2", "9", "4", "1", "3", "7", "6", "1", "1", "2", "2", "9", "3", "1", "1", "69", "4", "4", "5", "12", "1", "1", "5", "15", "1", "4" ]
[ "cofr", "nonn" ]
75
0
5
[ "A002351", "A002352", "A002580", "A002945", "A002946", "A002947", "A002948", "A002949" ]
[ "M2220" ]
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002945.seq
a40524dcf298fb50957e5af20da63f02
A002946
Continued fraction for cube root of 3.
[ "1", "2", "3", "1", "4", "1", "5", "1", "1", "6", "2", "5", "8", "3", "3", "4", "2", "6", "4", "4", "1", "3", "2", "3", "4", "1", "4", "9", "1", "8", "4", "3", "1", "3", "2", "6", "1", "6", "1", "3", "1", "1", "1", "1", "12", "3", "1", "3", "1", "1", "4", "1", "6", "1", "5", "1", "2", "1", "3", "3", "11", "8", "1", "139", "8", "2", "8", "5", "1", "2", "2", "2", "2", "3", "1", "1", "2", "1", "1", "1", "52", "2", "46", "2", "2", "3" ]
[ "nonn", "cofr" ]
44
0
5
[ "A002353", "A002354", "A002581", "A002946" ]
[ "M0408" ]
N. J. A. Sloane
2024-07-04T19:57:43
oeisdata/seq/A002/A002946.seq
517642c007cc1ea5671616b1c1fad971
A002947
Continued fraction for cube root of 4.
[ "1", "1", "1", "2", "2", "1", "3", "2", "3", "1", "3", "1", "30", "1", "4", "1", "2", "9", "6", "4", "1", "1", "2", "7", "2", "3", "2", "1", "6", "1", "1", "1", "25", "1", "7", "7", "1", "1", "1", "1", "266", "1", "3", "2", "1", "3", "60", "1", "5", "1", "8", "5", "6", "1", "4", "20", "1", "4", "1", "1", "14", "1", "4", "4", "1", "1", "1", "1", "7", "3", "1", "1", "2", "1", "3", "1", "4", "4", "1", "1", "1", "3", "1", "34", "8", "2", "10", "6", "3", "1", "2", "31", "1", "1", "1", "4", "3", "44", "1", "45" ]
[ "nonn", "cofr", "easy" ]
40
0
5
[ "A002355", "A002356", "A002947", "A005480" ]
[ "M0200" ]
N. J. A. Sloane
2024-07-04T19:58:10
oeisdata/seq/A002/A002947.seq
d79fccaef79f6d03ee091ef044d94b69
A002948
Continued fraction for cube root of 5.
[ "1", "1", "2", "2", "4", "3", "3", "1", "5", "1", "1", "4", "10", "17", "1", "14", "1", "1", "3052", "1", "1", "1", "1", "1", "1", "2", "2", "1", "3", "2", "1", "13", "5", "1", "1", "1", "13", "2", "41", "1", "4", "12", "1", "5", "2", "7", "1", "1", "3", "33", "2", "1", "1", "1", "1", "1", "1", "3", "2", "2", "1", "15", "12", "8", "10", "48", "1", "2", "1", "1", "3", "4", "1", "474", "1", "13", "2", "4", "1", "1", "49" ]
[ "nonn", "cofr" ]
40
0
5
[ "A002357", "A002358", "A002948", "A005481" ]
[ "M0300" ]
N. J. A. Sloane
2024-07-04T19:58:32
oeisdata/seq/A002/A002948.seq
3b31294eedcf8456d486d6c420d84d22
A002949
Continued fraction for cube root of 6.
[ "1", "1", "4", "2", "7", "3", "508", "1", "5", "5", "1", "1", "1", "2", "1", "1", "24", "1", "1", "1", "3", "3", "30", "4", "10", "158", "6", "1", "1", "2", "12", "1", "10", "1", "1", "3", "2", "1", "1", "89", "1", "1", "2", "1", "1", "1", "3", "1", "2", "1", "7", "1", "2", "18", "1", "17", "2", "2", "10", "14", "3", "1", "2", "1", "2", "1", "5", "1", "1", "2", "26", "1", "4", "65", "1", "1", "1", "27", "1", "2", "1", "4" ]
[ "nonn", "cofr" ]
49
0
5
[ "A002359", "A002360", "A002949", "A005486" ]
[ "M3202" ]
N. J. A. Sloane
2024-07-05T10:07:21
oeisdata/seq/A002/A002949.seq
c084ac87d1a241e6d70a87242d5a77b0
A002950
Continued fraction for fifth root of 2.
[ "1", "6", "1", "2", "1", "1", "1", "3", "25", "1", "4", "3", "3", "7", "52", "1", "2", "3", "2", "15", "2", "2", "4", "16", "2", "7", "1", "1", "1", "10", "21", "1", "1", "1", "141", "2", "4", "1", "4", "2", "1", "1", "17", "1", "3", "3", "4", "1", "3", "1", "3", "2", "1", "1", "2", "33", "1", "6", "6", "1", "2", "4", "1", "21", "1", "3", "3", "8", "10", "1", "46", "6", "1", "10", "1", "1", "1", "1", "2", "11", "1", "3", "1" ]
[ "nonn", "cofr" ]
45
0
5
[ "A002361", "A002362", "A002950", "A005531" ]
[ "M4044" ]
N. J. A. Sloane, Herman P. Robinson
2024-07-05T11:10:17
oeisdata/seq/A002/A002950.seq
add6e1556ed4ea6b26b788b3e54f1263
A002951
Continued fraction for fifth root of 5.
[ "1", "2", "1", "1", "1", "2", "1", "2", "8", "1", "25", "1", "5", "1", "22", "1", "8", "1", "1", "9", "1", "1", "4", "1", "2", "1", "2", "1", "2", "2", "1", "1", "1", "1", "2", "1", "6", "2", "46", "1", "12", "1", "32", "1", "2", "3", "2", "3", "55", "1", "12", "3", "8", "1", "1", "11", "1", "4", "1", "1", "1", "2", "1", "1", "7", "1", "1", "4", "3", "3", "3218", "1", "3", "1", "2", "2", "3", "1", "1", "2", "11", "1", "7", "57", "2", "2", "2", "2", "1", "1", "67", "1", "2", "3", "1", "1", "13", "3" ]
[ "nonn", "cofr" ]
48
0
5
[ "A002363", "A002364", "A002951", "A005534" ]
[ "M0059" ]
N. J. A. Sloane
2024-07-05T11:10:12
oeisdata/seq/A002/A002951.seq
5b184f9fa6f32f378906789e22a68f42
A002952
Smaller of unitary amicable pair.
[ "114", "1140", "18018", "32130", "44772", "56430", "67158", "142310", "180180", "197340", "241110", "296010", "308220", "462330", "591030", "669900", "671580", "785148", "815100", "1004850", "1077890", "1080150", "1156870", "1177722", "1222650", "1281540", "1475810", "1511930", "1571388" ]
[ "nonn", "nice" ]
34
0
5
[ "A002952", "A002953", "A063991", "A111904" ]
[ "M5372" ]
N. J. A. Sloane; extended Nov 24 2005
2025-02-16T08:32:27
oeisdata/seq/A002/A002952.seq
101683c62bf5cc9359829068d6c4d524
A002953
Larger of unitary amicable pair.
[ "126", "1260", "22302", "40446", "49308", "64530", "73962", "168730", "223020", "286500", "242730", "429750", "365700", "548550", "618570", "827700", "739620", "827652", "932100", "1241550", "1099390", "1291050", "1292570", "1241478", "1398150", "1621500", "1669150", "1598470", "1654212" ]
[ "nonn", "nice" ]
29
0
5
[ "A002952", "A002953", "A063991", "A111904" ]
[ "M5389" ]
N. J. A. Sloane; extended Nov 24 2005
2025-02-16T08:32:27
oeisdata/seq/A002/A002953.seq
2a883c36a5149ddf12b4f7c287790213
A002954
Smallest number such that n-th iterate of Chowla function is 0.
[ "2", "4", "8", "15", "12", "27", "24", "36", "90", "96", "245", "288", "368", "676", "1088", "2300", "1596", "1458", "3344", "3888", "5360", "8895", "11852", "25971", "23360", "38895", "35540", "35595", "36032", "53823", "47840", "62055", "59360", "83391", "70784", "128079", "145668", "349299", "254540", "327495", "293744", "328335", "167664" ]
[ "nonn" ]
31
0
5
[ "A002954", "A048050" ]
[ "M1099" ]
N. J. A. Sloane
2024-03-09T04:43:12
oeisdata/seq/A002/A002954.seq
15d507c0a259ce2bce33e6c7e023cd22
A002955
Number of (unordered, unlabeled) rooted trimmed trees with n nodes.
[ "1", "1", "1", "2", "4", "8", "17", "36", "79", "175", "395", "899", "2074", "4818", "11291", "26626", "63184", "150691", "361141", "869057", "2099386", "5088769", "12373721", "30173307", "73771453", "180800699", "444101658", "1093104961", "2695730992", "6659914175", "16481146479", "40849449618" ]
[ "nonn", "nice", "eigen" ]
52
0
5
[ "A002955", "A002988", "A002992", "A052318", "A052329", "A255636" ]
[ "M1140" ]
N. J. A. Sloane
2023-10-27T21:06:51
oeisdata/seq/A002/A002955.seq
47dae34625667539d1f2e4959a2a4cae
A002956
Number of basic invariants for cyclic group of order and degree n.
[ "1", "2", "4", "7", "15", "20", "48", "65", "119", "166", "348", "367", "827", "974", "1494", "2135", "3913", "4038", "7936", "8247", "12967", "17476", "29162", "28065", "49609", "59358", "83420", "97243", "164967", "152548", "280352", "295291", "405919", "508162", "674630", "708819", "1230259", "1325732", "1709230" ]
[ "nonn", "nice" ]
30
0
5
[ "A002956", "A082641", "A096337" ]
[ "M1084" ]
N. J. A. Sloane
2018-11-09T14:02:34
oeisdata/seq/A002/A002956.seq
bd50509ab454b9e9b98afc5801dc65a9
A002957
Numbers k such that 2*10^k - 1 is prime.
[ "1", "2", "3", "5", "7", "26", "27", "53", "147", "236", "248", "386", "401", "546", "785", "1325", "1755", "2906", "3020", "5407", "5697", "5969", "7517", "15749", "19233", "38232", "55347", "1059002" ]
[ "hard", "nonn", "more" ]
49
0
5
null
[ "M0680" ]
N. J. A. Sloane, Simon Plouffe
2023-01-17T07:11:42
oeisdata/seq/A002/A002957.seq
a399db32f812bbcc3d41d7aa3a93c628
A002958
Numbers k such that 2*25^k - 1 is prime.
[ "2", "3", "8", "12", "15", "27", "48", "89", "137", "666", "1383", "1530", "2102", "8868", "95031", "111768", "130200", "341540" ]
[ "nonn", "hard", "more" ]
37
0
5
null
[ "M0870" ]
N. J. A. Sloane, Simon Plouffe
2023-10-21T01:07:51
oeisdata/seq/A002/A002958.seq
75e0b7e01f585c48fc2be232b1c83efc
A002959
Numbers k such that 2*7^k - 1 is prime.
[ "1", "2", "4", "5", "14", "24", "29", "36", "46", "80", "474", "1018", "5180", "22581", "41649", "52744", "114564", "147454", "174180" ]
[ "nonn", "hard", "more" ]
31
0
5
null
[ "M0979" ]
N. J. A. Sloane
2023-10-21T23:47:12
oeisdata/seq/A002/A002959.seq
682b29275e01af908974a7a3b9a80333
A002960
The square sieve.
[ "2", "5", "8", "12", "17", "22", "28", "34", "41", "48", "56", "65", "74", "84", "94", "105", "116", "128", "140", "153", "166", "180", "194", "209", "224", "240", "257", "274", "292", "310", "329", "348", "368", "388", "409", "430", "452", "474", "497", "520", "544", "568", "593", "618", "644", "670", "697", "724", "752", "780", "809", "838", "868", "898", "929", "960", "992", "1025", "1058", "1092", "1126", "1161", "1196" ]
[ "nonn" ]
67
0
5
[ "A002960", "A274089" ]
[ "M1346" ]
N. J. A. Sloane
2024-05-03T10:32:02
oeisdata/seq/A002/A002960.seq
34c9edfe35c95d95694e16b8fc2e2e8d
A002961
Numbers k such that k and k+1 have same sum of divisors.
[ "14", "206", "957", "1334", "1364", "1634", "2685", "2974", "4364", "14841", "18873", "19358", "20145", "24957", "33998", "36566", "42818", "56564", "64665", "74918", "79826", "79833", "84134", "92685", "109214", "111506", "116937", "122073", "138237", "147454", "161001", "162602", "166934" ]
[ "nonn", "nice" ]
117
0
5
[ "A000203", "A002961", "A007373", "A015861", "A015863", "A015865", "A015866", "A015867", "A015876", "A015877", "A015880", "A015881", "A015882", "A015883", "A053215", "A053249", "A054004", "A181647", "A238380" ]
[ "M4950" ]
N. J. A. Sloane, Mira Bernstein, Robert G. Wilson v
2025-01-05T19:51:32
oeisdata/seq/A002/A002961.seq
d1784d4e6b52911fe6238a796a9316b6
A002962
Number of simple imperfect squared squares of order n up to symmetry.
[ "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "0", "1", "0", "3", "5", "15", "19", "57", "72", "274", "491", "1766", "3679", "11158", "24086", "64754", "132598", "326042", "667403", "1627218", "3508516" ]
[ "nonn", "hard", "nice", "more" ]
78
0
5
[ "A002839", "A002881", "A002962", "A006983", "A014530", "A181735", "A217155", "A217156" ]
[ "M2496" ]
N. J. A. Sloane
2024-08-01T03:05:01
oeisdata/seq/A002/A002962.seq
1cd739d77e78423fe234aa1ee1d32a6d
A002963
Number of chisel strokes required for Roman numerals for n.
[ "1", "2", "3", "3", "2", "3", "4", "5", "3", "2", "3", "4", "5", "5", "4", "5", "6", "7", "5", "4", "5", "6", "7", "7", "6", "7", "8", "9", "7", "6", "7", "8", "9", "9", "8", "9", "10", "11", "9", "4", "5", "6", "7", "7", "6", "7", "8", "9", "7", "2", "3", "4", "5", "5", "4", "5", "6", "7", "5", "4", "5", "6", "7", "7", "6", "7", "8", "9", "7", "6", "7", "8", "9", "9", "8", "9", "10", "11", "9", "8", "9", "10", "11", "11", "10", "11", "12", "13", "11", "4", "5", "6", "7", "7", "6", "7", "8", "9", "7", "2", "3", "4" ]
[ "base", "easy", "nonn", "nice" ]
42
0
5
[ "A002963", "A061493", "A093783", "A119310" ]
null
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002963.seq
77db2e196cd57071bfdcc3a1a85f9c22
A002964
Smallest number requiring n chisel strokes for its representation in Roman numerals.
[ "1", "2", "3", "7", "8", "17", "18", "27", "28", "37", "38", "87", "88", "187", "188", "287", "288", "387", "388", "788", "887", "888", "1388", "1788", "1887", "1888", "2388", "2788", "2887", "2888", "3388", "3788", "3887", "3888" ]
[ "base", "nonn", "nice" ]
22
0
5
[ "A002963", "A002964" ]
null
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002964.seq
023c3583fefbf0d172671c4f06aaa458
A002965
Interleave denominators (A000129) and numerators (A001333) of convergents to sqrt(2).
[ "0", "1", "1", "1", "2", "3", "5", "7", "12", "17", "29", "41", "70", "99", "169", "239", "408", "577", "985", "1393", "2378", "3363", "5741", "8119", "13860", "19601", "33461", "47321", "80782", "114243", "195025", "275807", "470832", "665857", "1136689", "1607521", "2744210", "3880899", "6625109", "9369319", "15994428", "22619537" ]
[ "nonn", "easy", "nice", "frac" ]
147
0
5
[ "A000129", "A001109", "A001333", "A002965", "A155046" ]
[ "M0671" ]
N. J. A. Sloane
2024-08-01T03:04:35
oeisdata/seq/A002/A002965.seq
3172435214ab4a1cf00ea35c16c55d7a
A002966
Egyptian fractions: number of solutions of 1 = 1/x_1 + ... + 1/x_n where 0 < x_1 <= ... <= x_n.
[ "1", "1", "3", "14", "147", "3462", "294314", "159330691" ]
[ "nonn", "nice", "hard", "more" ]
91
0
5
[ "A000058", "A002966", "A002967", "A006585", "A348625" ]
[ "M2981" ]
N. J. A. Sloane, Robert G. Wilson v
2024-07-30T14:41:47
oeisdata/seq/A002/A002966.seq
c6a96c380b70b2baf2cfed5c8c7368c2
A002967
Egyptian fractions: number of solutions of 1 = 1/x_1 + ... + 1/x_n in positive integers.
[ "1", "1", "10", "215", "12231", "2025462", "1351857641", "6255560531733" ]
[ "nonn", "nice", "hard", "more" ]
58
0
5
[ "A000058", "A002966", "A002967", "A006585" ]
[ "M4745" ]
N. J. A. Sloane
2024-02-16T05:47:40
oeisdata/seq/A002/A002967.seq
ee3758d93d0dfb98109423127e06477a
A002968
Number of pairings {(b(1), c(1)), (b(2), c(2)), ..., (b(n), c(n))} of the first 2n positive integers satisfying b(i) < c(i) and such that the 2n numbers c(i)+b(i) and c(i)-b(i) are all distinct.
[ "1", "1", "0", "1", "8", "22", "51", "342", "2609", "16896", "99114", "876579", "8551800", "79595269", "764804085", "8905825760" ]
[ "nonn", "more" ]
40
0
5
[ "A002968", "A007631" ]
[ "M4494" ]
N. J. A. Sloane
2023-10-21T01:20:25
oeisdata/seq/A002/A002968.seq
088292fbf5ef79c9047fe1f41a548954
A002969
E.g.f. 1/(1 - sin(x) + sin(x)^2).
[ "1", "1", "0", "-7", "-24", "61", "1200", "4493", "-48384", "-781319", "-1804800", "85444193", "1210361856", "-1847527499", "-288162201600", "-3428482320907", "33720680349696", "1637781983297521", "14158399925452800", "-431041350297034807", "-14236987086964260864" ]
[ "sign" ]
14
0
5
[ "A002969", "A029585" ]
null
N. J. A. Sloane
2018-01-27T18:21:05
oeisdata/seq/A002/A002969.seq
9ba6af094c51e3955c8ec5b4be07891c
A002970
Numbers k such that 4*k^2 + 9 is prime.
[ "1", "4", "5", "10", "16", "19", "20", "26", "29", "31", "35", "41", "44", "49", "50", "55", "56", "59", "70", "71", "80", "85", "94", "95", "100", "101", "106", "109", "110", "121", "149", "154", "160", "166", "175", "179", "184", "190", "191", "200", "205", "206", "211", "224", "236", "241", "245", "251", "256", "265", "269", "271", "284", "286", "289", "299", "304", "314" ]
[ "nonn", "easy" ]
31
0
5
null
[ "M3248" ]
N. J. A. Sloane
2023-10-21T01:07:43
oeisdata/seq/A002/A002970.seq
4c5ecd1d0e9f78ac504e7a71963552a6
A002971
Numbers k such that 4*k^2 + 25 is prime.
[ "1", "2", "3", "4", "8", "9", "11", "12", "13", "14", "16", "17", "18", "21", "23", "26", "29", "34", "36", "37", "38", "47", "48", "49", "51", "53", "54", "56", "62", "63", "66", "67", "68", "69", "73", "74", "77", "79", "82", "83", "91", "99", "101", "102", "103", "107", "108", "114", "116", "118", "122", "131", "134", "141", "142", "147", "148", "151", "154", "156", "157", "158", "159", "164" ]
[ "nonn", "easy" ]
29
0
5
null
[ "M0587" ]
N. J. A. Sloane
2023-10-20T22:00:27
oeisdata/seq/A002/A002971.seq
4f20af8cbaca6be1f5bc462762a703c9
A002972
a(n) is the odd member of {x,y}, where x^2 + y^2 is the n-th prime of the form 4i+1.
[ "1", "3", "1", "5", "1", "5", "7", "5", "3", "5", "9", "1", "3", "7", "11", "7", "11", "13", "9", "7", "1", "15", "13", "15", "1", "13", "9", "5", "17", "13", "11", "9", "5", "17", "7", "17", "19", "1", "3", "15", "17", "7", "21", "19", "5", "11", "21", "19", "13", "1", "23", "5", "17", "19", "25", "13", "25", "23", "1", "5", "15", "27", "9", "19", "25", "17", "11", "5", "25", "27", "23", "29", "29", "25", "23", "19", "29", "13", "31", "31" ]
[ "nonn", "changed" ]
81
0
5
[ "A002144", "A002972", "A002973", "A005098", "A261858" ]
[ "M2221" ]
N. J. A. Sloane
2025-04-20T05:10:19
oeisdata/seq/A002/A002972.seq
23a7bbd606cbc2f4075e9d30175c461f
A002973
a(n) is half of the even member of {x,y}, where x^2 + y^2 is the n-th prime of the form 4i+1.
[ "1", "1", "2", "1", "3", "2", "1", "3", "4", "4", "2", "5", "5", "4", "2", "5", "3", "1", "5", "6", "7", "1", "4", "2", "8", "5", "7", "8", "1", "6", "7", "8", "9", "4", "9", "5", "3", "10", "10", "7", "6", "10", "2", "5", "11", "10", "5", "7", "10", "12", "4", "12", "9", "8", "2", "11", "3", "6", "13", "13", "11", "1", "13", "10", "6", "11", "13", "14", "7", "5", "9", "2", "3", "8", "10", "12", "5", "14", "2", "3", "14", "11", "15", "16", "16", "5", "15", "1", "8", "11" ]
[ "nonn" ]
48
0
5
[ "A002144", "A002972", "A002973", "A005098" ]
[ "M0135" ]
N. J. A. Sloane
2023-10-29T01:49:54
oeisdata/seq/A002/A002973.seq
7d9b44791353e9ccded0194f10e736e7
A002974
Number of restricted solid partitions of n.
[ "1", "1", "4", "7", "11", "20", "35", "59", "99", "165", "270", "443", "723", "1161", "1861", "2961", "4654", "7279", "11317", "17476", "26879", "41132", "62601", "94878", "143172", "215115", "321995", "480216", "713655", "1057192" ]
[ "nonn", "more" ]
29
0
5
[ "A000219", "A000293", "A000334", "A001970", "A002974", "A114736", "A117433", "A321662", "A323657" ]
[ "M3304" ]
N. J. A. Sloane
2019-01-23T19:59:42
oeisdata/seq/A002/A002974.seq
72940536095a87e83ce662f4b3a80ef5
A002975
Primitive weird numbers: weird numbers with no proper weird divisors.
[ "70", "836", "4030", "5830", "7192", "7912", "9272", "10792", "17272", "45356", "73616", "83312", "91388", "113072", "243892", "254012", "338572", "343876", "388076", "519712", "539744", "555616", "682592", "786208", "1188256", "1229152", "1713592", "1901728", "2081824", "2189024", "3963968", "4128448" ]
[ "nonn", "nice" ]
351
0
5
[ "A002975", "A006037", "A258333", "A258374", "A258375", "A258401", "A258882", "A258883", "A258884", "A258885" ]
[ "M5340" ]
N. J. A. Sloane
2020-02-15T01:25:38
oeisdata/seq/A002/A002975.seq
46568972828d2dcd02cbd565e426358b
A002976
Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).
[ "0", "1", "0", "2", "0", "5", "9", "21", "42", "76", "174", "396", "888", "2023", "4345", "9921", "22566" ]
[ "nonn", "walk", "more" ]
23
0
5
[ "A001411", "A002976", "A037245" ]
[ "M0034" ]
N. J. A. Sloane
2018-12-27T07:57:25
oeisdata/seq/A002/A002976.seq
5ce72db5680b3b5abf37927f0ade248f
A002977
Klarner-Rado sequence: a(1) = 1; subsequent terms are defined by the rule that if m is present so are 2m+1 and 3m+1.
[ "1", "3", "4", "7", "9", "10", "13", "15", "19", "21", "22", "27", "28", "31", "39", "40", "43", "45", "46", "55", "57", "58", "63", "64", "67", "79", "81", "82", "85", "87", "91", "93", "94", "111", "115", "117", "118", "121", "127", "129", "130", "135", "136", "139", "159", "163", "165", "166", "171", "172", "175", "183", "187", "189", "190", "193", "202", "223", "231", "235", "237" ]
[ "easy", "nonn", "nice" ]
68
0
5
[ "A002977", "A007448", "A058361", "A076291", "A077477", "A276786" ]
[ "M2335" ]
N. J. A. Sloane
2022-01-13T01:31:14
oeisdata/seq/A002/A002977.seq
acdba6d561d4e519b2820713dd7891a6
A002978
Low-temperature series in y = exp(2J/kT) for antiferromagnetic susceptibility for the Ising model on honeycomb structure.
[ "0", "0", "4", "0", "12", "8", "48", "96", "320", "888", "2748", "8384", "26340", "83568", "268864", "873648", "2865216", "9470784", "31525524", "105594912", "355673804", "1204059144", "4094727168", "13983145888", "47932777680", "164881688088", "568990371212", "1969356192624", "6834965581764", "23782468159920" ]
[ "nonn", "nice" ]
22
0
5
[ "A002910", "A002912", "A002978", "A007214", "A007218", "A047709", "A057391", "A057395", "A128834" ]
[ "M3189" ]
N. J. A. Sloane
2021-03-03T09:37:31
oeisdata/seq/A002/A002978.seq
33425ecc3a66941e0d11a6702e1dfcb9
A002979
Low-temperature series in exp(4J/kT) for antiferromagnetic susceptibility for the Ising model on square lattice.
[ "0", "4", "0", "16", "32", "156", "608", "2688", "12064", "55956", "266656" ]
[ "nonn", "nice", "more" ]
23
0
5
[ "A002915", "A002927", "A002978", "A002979", "A007215" ]
[ "M3193" ]
N. J. A. Sloane
2022-02-22T00:29:14
oeisdata/seq/A002/A002979.seq
e8a728cebdf37aab68cdbd0233d721a8
A002980
E.g.f: 1/(1 - sin(x) + sin(x)^2 - sin(x)^3).
[ "1", "1", "0", "-1", "24", "121", "-480", "-4201", "48384", "478801", "-4968960", "-62871601", "885586944", "12996863881", "-203910819840", "-3476839930201", "63397697224704", "1221998040867361", "-24917358603141120", "-537278342731116001" ]
[ "sign" ]
15
0
5
null
null
N. J. A. Sloane
2023-10-21T01:07:47
oeisdata/seq/A002/A002980.seq
f587f1bee74e06bc3e8c478e8d9cd6f5
A002981
Numbers k such that k! + 1 is prime.
[ "0", "1", "2", "3", "11", "27", "37", "41", "73", "77", "116", "154", "320", "340", "399", "427", "872", "1477", "6380", "26951", "110059", "150209", "288465", "308084", "422429" ]
[ "nonn", "nice", "hard", "more" ]
185
0
5
[ "A002981", "A002982", "A064295", "A088332", "A090660", "A093804" ]
[ "M0908" ]
N. J. A. Sloane
2025-03-19T08:23:30
oeisdata/seq/A002/A002981.seq
f0270f673cf68c8a3c8b64a9eb6568f5
A002982
Numbers k such that k! - 1 is prime.
[ "3", "4", "6", "7", "12", "14", "30", "32", "33", "38", "94", "166", "324", "379", "469", "546", "974", "1963", "3507", "3610", "6917", "21480", "34790", "94550", "103040", "147855", "208003" ]
[ "hard", "more", "nonn", "nice" ]
153
0
5
[ "A000142", "A001221", "A001222", "A002981", "A002982", "A046051", "A054991", "A055490", "A088332", "A112798", "A325272" ]
[ "M2321" ]
N. J. A. Sloane
2025-03-19T08:23:52
oeisdata/seq/A002/A002982.seq
b51684cfde25cdfdc61df27cdf958abb
A002983
Expansion of e.g.f. 1/(1 - x*exp(x) + x^2*exp(2*x)).
[ "1", "1", "2", "-3", "-92", "-1015", "-8274", "-35483", "496280", "18127377", "344895130", "4427896781", "15653147412", "-1300426685831", "-53961316375498", "-1345994948213355", "-20836853905979984", "60576513730122017", "19579099820703961266", "894668319876527296669", "26059066415716831363820" ]
[ "sign" ]
15
0
5
null
null
N. J. A. Sloane
2020-03-17T07:25:09
oeisdata/seq/A002/A002983.seq
4412fae90428a75ea89c9284fd278f16
A002984
a(0) = 1; for n > 0, a(n) = a(n-1) + floor(sqrt(a(n-1))).
[ "1", "2", "3", "4", "6", "8", "10", "13", "16", "20", "24", "28", "33", "38", "44", "50", "57", "64", "72", "80", "88", "97", "106", "116", "126", "137", "148", "160", "172", "185", "198", "212", "226", "241", "256", "272", "288", "304", "321", "338", "356", "374", "393", "412", "432", "452", "473", "494", "516", "538", "561", "584", "608", "632", "657", "682", "708", "734" ]
[ "nonn", "easy", "nice" ]
57
0
5
[ "A000302", "A002984", "A109965" ]
[ "M0554" ]
N. J. A. Sloane
2024-02-14T15:03:34
oeisdata/seq/A002/A002984.seq
841aeeddde2ff4f1baea48bed1b47149
A002985
Number of trees in an n-node wheel.
[ "1", "1", "1", "2", "3", "6", "11", "20", "36", "64", "108", "179", "292", "464", "727", "1124", "1714", "2585", "3866", "5724", "8418", "12290", "17830", "25713", "36898", "52664", "74837", "105873", "149178", "209364", "292793", "407990", "566668", "784521", "1082848", "1490197", "2045093", "2798895", "3820629", "5202085" ]
[ "nonn" ]
28
0
5
[ "A002985", "A003293", "A004146", "A008804" ]
[ "M0783" ]
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002985.seq
888d0856d08930058fb3ad9db494cc06
A002986
Number of non-cyclic hydrocarbons with n carbon atoms (excluding stereoisomers).
[ "1", "3", "4", "12", "27", "84", "247", "826", "2777", "9868", "35579", "131847", "495671", "1893819", "7320954", "28619581", "112923053", "449343946", "1801330288", "7269849395", "29517342098", "120507480668", "494449558111", "2038073860257", "8436185990286", "35055744550563", "146195133355612", "611723431211193" ]
[ "nonn" ]
77
0
5
[ "A000602", "A002986" ]
[ "M2376" ]
N. J. A. Sloane
2022-06-25T17:07:39
oeisdata/seq/A002/A002986.seq
da5b51016b36ce7d277c73f6ff49d897
A002987
a(1) = 1; a(2) = 2; a(n) == a(k) (mod n-k) for all 1 < k < n.
[ "1", "2", "1", "4", "5", "46", "37", "176", "289", "1450", "641", "24652", "15061", "18734", "110125", "46216", "3137", "1460386", "10506529", "78796820", "77855941", "123250702", "55222421", "3066673744", "54926785", "4846380026", "20185744177", "58863278476", "7499028629", "1410916015630" ]
[ "nonn" ]
16
0
5
null
[ "M0169" ]
N. J. A. Sloane
2023-10-20T22:05:38
oeisdata/seq/A002/A002987.seq
199c2766fc08d906487c0ccc5280c78c
A002988
Number of trimmed trees with n nodes.
[ "1", "1", "1", "0", "1", "1", "2", "3", "6", "10", "21", "39", "82", "167", "360", "766", "1692", "3726", "8370", "18866", "43029", "98581", "227678", "528196", "1232541", "2888142", "6798293", "16061348", "38086682", "90607902", "216230205", "517482053", "1241778985", "2987268628", "7203242490" ]
[ "nonn", "nice" ]
41
0
5
[ "A002955", "A002988", "A002989", "A002992", "A052318", "A052329" ]
[ "M0777" ]
N. J. A. Sloane
2022-01-31T06:47:19
oeisdata/seq/A002/A002988.seq
53bcd63acec94972eb11fc2fbb4bd743
A002989
Number of n-node trees with a forbidden limb of length 3.
[ "1", "1", "1", "1", "1", "2", "4", "7", "14", "28", "61", "131", "297", "678", "1592", "3770", "9096", "22121", "54451", "135021", "337651", "849698", "2152048", "5479408", "14022947", "36048514", "93061268", "241160180", "627179689", "1636448181", "4282964600", "11241488853", "29584389474" ]
[ "nonn" ]
37
0
5
[ "A002955", "A002988", "A002989", "A002992", "A052318", "A052329" ]
[ "M1082" ]
N. J. A. Sloane
2023-10-21T01:07:39
oeisdata/seq/A002/A002989.seq
7aa115ce1902dbf5ac0f91eeeb976330
A002990
Number of n-node trees with a forbidden limb of length 4.
[ "1", "1", "1", "1", "2", "2", "5", "9", "19", "38", "86", "188", "439", "1026", "2472", "5997", "14835", "36964", "93246", "236922", "607111", "1565478", "4062797", "10599853", "27797420", "73224806", "193709710", "514406793", "1370937140", "3665714528", "9831891555", "26445886506", "71325268179" ]
[ "nonn" ]
35
0
5
[ "A002955", "A002988", "A002989", "A002990", "A002991", "A002992", "A052318", "A052319", "A052320", "A052321", "A052322", "A052323", "A052324", "A052325", "A052326", "A052327", "A052328", "A052329" ]
[ "M0350" ]
N. J. A. Sloane
2023-10-21T01:14:46
oeisdata/seq/A002/A002990.seq
cd5b8f4073dac14cb9f517c55d400a45
A002991
Number of n-node trees with a forbidden limb of length 5.
[ "1", "1", "1", "1", "2", "3", "5", "10", "21", "43", "97", "215", "503", "1187", "2876", "7033", "17510", "43961", "111664", "285809", "737632", "1915993", "5008652", "13163785", "34774873", "92282214", "245930746", "657931603", "1766481135", "4758553683", "12858286083", "34844908142", "94681272368" ]
[ "nonn" ]
38
0
5
[ "A002955", "A002988", "A002991", "A002992", "A052318", "A052329" ]
[ "M0725" ]
N. J. A. Sloane
2023-10-21T01:07:36
oeisdata/seq/A002/A002991.seq
bfae95a5e020234e9766593c570f11cb
A002992
Number of n-node trees with a forbidden limb of length 6.
[ "1", "1", "1", "1", "2", "3", "6", "10", "22", "45", "102", "226", "531", "1253", "3044", "7456", "18604", "46798", "119133", "305567", "790375", "2057523", "5390759", "14200122", "37598572", "100005401", "267131927", "716318650", "1927758155", "5205240762", "14098580633", "38296720823", "104308468102", "284822276099" ]
[ "nonn" ]
37
0
5
[ "A002955", "A002988", "A002991", "A002992", "A052318", "A052329" ]
[ "M0778" ]
N. J. A. Sloane
2023-10-21T01:07:28
oeisdata/seq/A002/A002992.seq
7dcbefca6865424c825e1aad0ea2a842
A002993
Initial digits of squares.
[ "0", "1", "4", "9", "1", "2", "3", "4", "6", "8", "1", "1", "1", "1", "1", "2", "2", "2", "3", "3", "4", "4", "4", "5", "5", "6", "6", "7", "7", "8", "9", "9", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "2", "2", "2", "2", "2", "2", "2", "2", "2", "2", "3", "3", "3", "3", "3", "3", "3", "3", "3", "4", "4", "4", "4", "4", "4", "4", "5", "5", "5", "5", "5", "5", "5", "6", "6", "6", "6", "6", "6", "7", "7", "7", "7", "7", "7", "8", "8", "8", "8", "8", "9", "9", "9", "9", "9", "1" ]
[ "nonn", "base" ]
38
0
5
[ "A000030", "A000290", "A002993", "A002994", "A089951" ]
[ "M3348" ]
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002993.seq
72fb43d6f4ba8950d61716a82e814160
A002994
Initial digit of cubes.
[ "0", "1", "8", "2", "6", "1", "2", "3", "5", "7", "1", "1", "1", "2", "2", "3", "4", "4", "5", "6", "8", "9", "1", "1", "1", "1", "1", "1", "2", "2", "2", "2", "3", "3", "3", "4", "4", "5", "5", "5", "6", "6", "7", "7", "8", "9", "9", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "1", "2", "2", "2", "2", "2", "2", "2", "2", "3", "3", "3", "3", "3", "3", "3", "4", "4", "4", "4", "4", "4", "5", "5", "5", "5", "5", "6", "6", "6", "6", "7", "7", "7", "7", "8", "8", "8", "8", "9", "9", "9", "1" ]
[ "nonn", "easy", "base" ]
37
0
5
[ "A000030", "A000578", "A002993", "A002994", "A144582" ]
[ "M4468" ]
N. J. A. Sloane
2025-02-16T08:32:27
oeisdata/seq/A002/A002994.seq
281a219f4372b1c1f78186ec5a69af77
A002995
Number of unlabeled planar trees (also called plane trees) with n nodes.
[ "1", "1", "1", "1", "2", "3", "6", "14", "34", "95", "280", "854", "2694", "8714", "28640", "95640", "323396", "1105335", "3813798", "13269146", "46509358", "164107650", "582538732", "2079165208", "7457847082", "26873059986", "97239032056", "353218528324", "1287658723550", "4709785569184" ]
[ "nonn", "easy", "nice" ]
116
0
5
[ "A000055", "A000108", "A002995", "A002996", "A003239", "A005354", "A057502", "A061417", "A064640", "A303694", "A303864" ]
[ "M0805" ]
N. J. A. Sloane
2024-10-12T09:05:47
oeisdata/seq/A002/A002995.seq
4c4a44c03b23af9ae10c09e1d161eb64
A002996
a(n) = Sum_{k|n} mu(k)*Catalan(n/k) (mu = Moebius function A008683).
[ "1", "1", "4", "12", "41", "126", "428", "1416", "4857", "16753", "58785", "207868", "742899", "2674010", "9694799", "35356240", "129644789", "477633711", "1767263189", "6564103612", "24466266587", "91482504853", "343059613649", "1289903937896", "4861946401410", "18367352329251", "69533550911142", "263747949075908", "1002242216651367" ]
[ "nonn", "easy", "nice" ]
42
0
5
[ "A002995", "A002996", "A027750" ]
[ "M3454" ]
N. J. A. Sloane
2023-07-06T06:39:24
oeisdata/seq/A002/A002996.seq
4427748b71d15a915043946b8b31df9e
A002997
Carmichael numbers: composite numbers k such that a^(k-1) == 1 (mod k) for every a coprime to k.
[ "561", "1105", "1729", "2465", "2821", "6601", "8911", "10585", "15841", "29341", "41041", "46657", "52633", "62745", "63973", "75361", "101101", "115921", "126217", "162401", "172081", "188461", "252601", "278545", "294409", "314821", "334153", "340561", "399001", "410041", "449065", "488881", "512461", "530881", "552721" ]
[ "nonn", "nice" ]
429
0
5
[ "A001567", "A002322", "A002445", "A002997", "A006931", "A024556", "A027748", "A055553", "A064238", "A064262", "A083737", "A087441", "A087442", "A135717", "A141711", "A153581", "A225498", "A285512", "A285549", "A309132", "A324050", "A324290", "A324315", "A324316", "A324973", "A324975", "A324977", "A326690" ]
[ "M5462" ]
N. J. A. Sloane
2025-04-05T10:27:22
oeisdata/seq/A002/A002997.seq
708ea956d294bc32d5add611bc70ffb2
A002998
Smallest multiple of n whose digits sum to n.
[ "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "190", "209", "48", "247", "266", "195", "448", "476", "198", "874", "3980", "399", "2398", "1679", "888", "4975", "1898", "999", "7588", "4988", "39990", "8959", "17888", "42999", "28798", "57995", "29988", "37999", "59888", "49998", "699880", "177899", "88998", "99889", "479996", "499995" ]
[ "nonn", "base", "easy", "nice" ]
57
0
5
[ "A002998", "A005349", "A131382" ]
[ "M0489" ]
N. J. A. Sloane
2023-06-30T08:19:03
oeisdata/seq/A002/A002998.seq
1b63c5cc6e963ed18b4502c427d4e2ba
A002999
Expansion of (1 + x*exp(x))^2.
[ "1", "2", "6", "18", "56", "170", "492", "1358", "3600", "9234", "23060", "56342", "135192", "319514", "745500", "1720350", "3932192", "8912930", "20054052", "44826662", "99614760", "220201002", "484442156", "1061158958", "2315255856", "5033164850", "10905190452", "23555211318", "50734301240", "108984795194" ]
[ "nonn", "easy" ]
26
0
5
[ "A001787", "A001815", "A002999", "A003013", "A005183", "A048482" ]
null
N. J. A. Sloane
2023-10-21T01:12:09
oeisdata/seq/A002/A002999.seq
5cc2799208e627b456d641a2ff4dc25f
A003000
Number of bifix-free (or primary, or unbordered) words of length n over a two-letter alphabet.
[ "1", "2", "2", "4", "6", "12", "20", "40", "74", "148", "284", "568", "1116", "2232", "4424", "8848", "17622", "35244", "70340", "140680", "281076", "562152", "1123736", "2247472", "4493828", "8987656", "17973080", "35946160", "71887896", "143775792", "287542736", "575085472", "1150153322", "2300306644", "4600578044", "9201156088" ]
[ "nonn", "easy", "nice" ]
113
0
5
[ "A003000", "A019308", "A019309", "A045690", "A094536", "A094537", "A242430" ]
[ "M0328" ]
N. J. A. Sloane
2024-09-29T09:19:55
oeisdata/seq/A003/A003000.seq
f65fba30d51cb7a0e59261d2bbcd8407