cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 41 results. Next

A007326 Difference between A000294 and the number of solid partitions of n (A000293).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 1, 3, 8, 19, 40, 83, 176, 365, 775, 1643, 3483, 7299, 15170, 31010, 62563, 124221, 243296, 469856, 896491, 1690475, 3155551, 5834871, 10701036, 19479021, 35227889, 63335778, 113286272, 201687929, 357585904, 631574315, 1111614614, 1950096758, 3410420973, 5946337698, 10337420278, 17918573379, 30968896662, 53366449357, 91689380979, 157058043025, 268210414468, 456613323892
Offset: 0

Views

Author

Keywords

Comments

Understanding this sequence is a famous unsolved problem in the theory of partitions.

References

  • G. E. Andrews, The Theory of Partitions, Addison-Wesley, 1976, p. 190.
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Extensions

Entry revised by Sean A. Irvine and N. J. A. Sloane, Dec 18 2017

A037452 Let F(x) = 1 + 1*x + 4*x^2 + 10*x^3 + ..., the g.f. for A000293 (solid partitions), and write F(x) = 1/Product_{n>=1} (1 - x^n)^a(n).

Original entry on oeis.org

0, 1, 3, 6, 10, 15, 20, 26, 34, 46, 68, 97, 120, 112, 23, -186, -496, -735, -531, 779, 3894, 9323, 16472, 23056, 23850, 10116, -31613, -120720, -283202, -548924, -932162, -1380125, -1655072, -1144651, 1385629, 7943203, 21083967, 42787785, 71816191, 98995196, 100392874, 29623771, -187433150
Offset: 0

Views

Author

N. J. A. Sloane, May 02 2003

Keywords

Crossrefs

Extensions

More terms from Vladeta Jovovic, Jul 30 2003

A002836 Let F(x) = 1 + x + 4x^2 + 10x^3 + ... = g.f. for A000293 (solid partitions) and expand (1-x)(1-x^2)(1-x^3)...*F(x) in powers of x.

Original entry on oeis.org

1, 0, 2, 5, 12, 24, 56, 113, 248, 503, 1043, 2080, 4169, 8145, 15897, 30545, 58402, 110461, 207802, 387561, 718875, 1324038, 2425473, 4416193, 7999516, 14411507, 25837198, 46092306, 81851250, 144691532, 254682865, 446399687, 779302305
Offset: 0

Views

Author

Keywords

Comments

Convolved with A000041 = A000293, solid partitions; and left border of the convolution triangle A161564. - Gary W. Adamson, Jun 13 2009

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Extensions

More terms from Pab Ter (pabrlos(AT)yahoo.com), May 08 2004
More terms from Srivatsan Balakrishnan and Suresh Govindarajan, Jan 03 2013

A161564 Convolution triangle for A000293 (solid partitions): A000041 * A002836.

Original entry on oeis.org

1, 0, 1, 2, 0, 2, 5, 2, 0, 3, 12, 5, 4, 0, 5, 24, 12, 10, 6, 0, 7, 56, 24, 24, 15, 10, 0, 11, 113, 56, 48, 36, 25, 14, 0, 15, 248, 113, 112, 72, 60, 35, 22, 0, 22, 503, 248, 226, 168, 120, 84, 55, 30, 0, 30
Offset: 0

Views

Author

Gary W. Adamson, Jun 13 2009

Keywords

Comments

Row sums = A000293, solid partitions: (1, 1, 4, 10, 26, 59, 140, 307, 684,...)

Examples

			First few rows of the triangle =
1;
0, 1;
2, 0, 2;
5, 2, 0, 3;
12, 5, 4, 0, 5;
24, 12, 10, 6, 0, 7;
56, 24, 24, 15, 10, 0, 11;
113, 56, 48, 36, 25, 14, 0, 15;
248, 113, 112, 72, 60, 35, 22, 0, 22;
503, 248, 226, 168, 120, 84, 55, 30, 0, 30;
...
Example: row 4 = (12, 5, 4, 0, 5), sum = 26 = A000293(4).
		

Crossrefs

Formula

Triangle read by rows, A000041 convolved with A002836: (1, 0, 2, 5, 12, 24, 56,...). Antidiagonals of a convolution array, A002836 * A000041: 1, . 1, . 2, . 3, . 5, . 7, . 11,... 0, . 0, . 0, . 0, . 0, . 0, .. 0,... 2, . 2, . 4, . 6, .10, .14, ..22,... 5, . 5, . 10, .15, .25, .35, ..55,... 12 .12, . 24, .36, .60, .84, .132,... ...

A193718 Let F(x) = 1 + 1*x + 4*x^2 + 10*x^3 + ..., the g.f. for A000293 (solid partitions), and write F(x) = 1/Product_{n>=1} E(n)^a(n) where E(n) = Product_{k>=n} (1 - x^(n*k)).

Original entry on oeis.org

1, 2, 5, 7, 14, 12, 25, 24, 40, 51, 96, 93, 111, -5, -206, -530, -736, -591, 778, 3819, 9292, 16373, 23055, 23706, 10101, -31727, -120766, -283232, -548925, -932041, -1380126, -1654576, -1144753, 1386362, 7943163, 21084398, 42787784, 71815410, 98995079, 100388956, 29623770, -187442482, -648478235, -1449118398, -2615085854, -3963369427, -4855203952, -3819950381, 1908741941, 16724652946
Offset: 0

Views

Author

Joerg Arndt, Aug 03 2011

Keywords

Crossrefs

Cf. A037452 (expansion 1/Product_{n>=1} (1 - x^n)^a(n)), A000293 (solid partitions).

A277613 Logarithmic derivative of the g.f. of the solid partitions A000293.

Original entry on oeis.org

1, 7, 19, 47, 76, 145, 183, 319, 433, 762, 1068, 1625, 1457, 511, -2696, -7617, -12494, -8999, 14802, 78682, 195984, 363458, 530289, 574297, 252976, -820475, -3259007, -7929105, -15918795, -27966750, -42783874, -52969921, -37772397, 47098898, 278012363, 759015293, 1583148046, 2729030066, 3860814119, 4015793914, 1214574612, -7871995868, -27884564061, -63760120938, -117678872282, -182313402679, -228194585696, -183355932567, 93528356566, 836233409412, 2360489258476, 4956621402741, 8577450776595, 12176709992155, 12572248705543, 2874527812671, -29026344726969, -100513507605919, -229939345736773, -423043591887710, -643162163240861, -757839109104688, -458886747576888, 831588355306815, 4020413344163097, 10249469548463477, 20417504944664974, 33937902760293134, 46224437161712292, 44445354551818961, 1635692222011481, -129140996172417587
Offset: 1

Views

Author

Paul D. Hanna, Nov 20 2016

Keywords

Comments

Based on the solid partitions calculated by Suresh Govindarajan and listed in A000293.
Finding a formula for this sequence is an unsolved problem; at first it was thought to be A278403, where: Sum_{n>=1} A278403(n)*x^n/n = log( Product_{n>=1} 1/(1 - x^n)^(n*(n+1)/2) ).

Examples

			L.g.f.: L(x) = x + 7*x^2/2 + 19*x^3/3 + 47*x^4/4 + 76*x^5/5 + 145*x^6/6 + 183*x^7/7 + 319*x^8/8 + 433*x^9/9 + 762*x^10/10 + 1068*x^11/11 + 1625*x^12/12 +...
such that
exp(L(x)) = 1 + x + 4*x^2 + 10*x^3 + 26*x^4 + 59*x^5 + 140*x^6 + 307*x^7 + 684*x^8 + 1464*x^9 + 3122*x^10 + 6500*x^11 + 13426*x^12 +...+ A000293(n)*x^n +...
		

Crossrefs

A143123 a(n) = Sum_{j=0..n} A000293(j).

Original entry on oeis.org

1, 2, 6, 16, 42, 101, 241, 548, 1232, 2696, 5818, 12318, 25744, 52992, 107796, 216598, 430669, 847518, 1652642, 3194279, 6124608, 11653341, 22015653, 41310879, 77024333, 142739427, 262996080, 481889660, 878308359, 1592707740
Offset: 0

Views

Author

Gary W. Adamson, Jul 26 2008

Keywords

Examples

			a(3) = 16 = (1 + 1 + 4 + 10).
		

Crossrefs

Cf. A000293.

Extensions

a(11) corrected and more terms from Georg Fischer, Aug 28 2020

A305842 Product_{n>=1} (1 + x^n)^a(n) = g.f. of A000293 (solid partitions).

Original entry on oeis.org

1, 4, 6, 14, 15, 26, 26, 48, 46, 83, 97, 146, 112, 49, -186, -448, -735, -485, 779, 3977, 9323, 16569, 23056, 23996, 10116, -31501, -120720, -283153, -548924, -932348, -1380125, -1655520, -1144651, 1384894, 7943203, 21083482, 42787785, 71816970, 98995196
Offset: 1

Views

Author

Ilya Gutkovskiy, Jun 11 2018

Keywords

Comments

Inverse weigh transform of A000293.

Examples

			(1 + x) * (1 + x^2)^4 * (1 + x^3)^6 * (1 + x^4)^14 * (1 + x^5)^15 * ... * (1 + x^n)^a(n) * ... = 1 + x + 4*x^2 + 10*x^3 + 26*x^4 + 59*x^5 + ... + A000293(k)*x^k + ...
		

Crossrefs

Formula

Product_{n>=1} (1 + x^n)^a(n) = Sum_{k>=0} A000293(k)*x^k.

A000294 Expansion of g.f. Product_{k >= 1} (1 - x^k)^(-k*(k+1)/2).

Original entry on oeis.org

1, 1, 4, 10, 26, 59, 141, 310, 692, 1483, 3162, 6583, 13602, 27613, 55579, 110445, 217554, 424148, 820294, 1572647, 2992892, 5652954, 10605608, 19765082, 36609945, 67405569, 123412204, 224728451, 407119735, 733878402, 1316631730, 2351322765, 4180714647, 7401898452, 13051476707, 22922301583, 40105025130, 69909106888, 121427077241, 210179991927, 362583131144
Offset: 0

Views

Author

Keywords

Comments

Number of partitions of n if there are k(k+1)/2 kinds of k (k=1,2,...). E.g., a(3)=10 because we have six kinds of 3, three kinds of 2+1 because there are three kinds of 2 and 1+1+1+1. - Emeric Deutsch, Mar 23 2005
Euler transform of the triangular numbers 1,3,6,10,...
Equals A028377: [1, 1, 3, 9, 19, 46, 100, ...] convolved with the aerated version of A000294: [1, 0, 1, 0, 4, 0, 10, 0, 26, 0, 59, ...]. - Gary W. Adamson, Jun 13 2009
The formula for p3(n) in the article by S. Finch (page 2) is incomplete, terms with n^(1/2) and n^(1/4) are also needed. These terms are in the article by Mustonen and Rajesh (page 2) and agree with my results, but in both articles the multiplicative constant is marked only as C, resp. c3(m). The following is a closed form of this constant: Pi^(1/24) * exp(1/24 - Zeta(3) / (8*Pi^2) + 75*Zeta(3)^3 / (2*Pi^8)) / (A^(1/2) * 2^(157/96) * 15^(13/96)) = A255939 = 0.213595160470..., where A = A074962 is the Glaisher-Kinkelin constant and Zeta(3) = A002117. - Vaclav Kotesovec, Mar 11 2015 [The new version of "Integer Partitions" by S. Finch contains the missing terms, see pages 2 and 5. - Vaclav Kotesovec, May 12 2015]
Number of solid partitions of corner-hook volume n (see arXiv:2009.00592 among links for definition). E.g., a(2) = 1 because there is only one solid partition [[[2]]] with cohook volume 2; a(3) = 4 because we have three solid partitions with two 1's (entry at (1,1,1) contributes 1, another entry at (2,1,1) or (1,2,1) or (1,1,2) contributes 2 to corner-hook volume) and one solid partition with single entry 3 (which contributes 3 to the corner-hook volume). Namely as 3D arrays [[[1],[1]]],[[[1]],[[1]]],[[[1]],[[1]]], [[[3]]]. - Alimzhan Amanov, Jul 13 2021

References

  • R. Chandra, Tables of solid partitions, Proceedings of the Indian National Science Academy, 26 (1960), 134-139.
  • V. S. Nanda, Tables of solid partitions, Proceedings of the Indian National Science Academy, 19 (1953), 313-314.
  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Cf. also A278403 (log of o.g.f.).

Programs

  • Maple
    with(numtheory): etr:= proc(p) local b; b:=proc(n) option remember; local d,j; if n=0 then 1 else add(add(d*p(d), d=divisors(j)) *b(n-j), j=1..n)/n fi end end: a:= etr(n-> n*(n+1)/2): seq(a(n), n=0..30);  # Alois P. Heinz, Sep 08 2008
  • Mathematica
    a[0] = 1; a[n_] := a[n] = 1/(2*n)*Sum[(DivisorSigma[2, k]+DivisorSigma[3, k])*a[n-k], {k, 1, n}]; Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Mar 05 2014, after Vladeta Jovovic *)
    nmax=50; CoefficientList[Series[Product[1/(1-x^k)^(k*(k+1)/2),{k,1,nmax}],{x,0,nmax}],x] (* Vaclav Kotesovec, Mar 11 2015 *)
  • PARI
    a(n)=if(n<0, 0, polcoeff(exp(sum(k=1, n, x^k/(1-x^k)^3/k, x*O(x^n))), n)) \\ Joerg Arndt, Apr 16 2010
    
  • SageMath
    # uses[EulerTransform from A166861]
    b = EulerTransform(lambda n: binomial(n+1, 2))
    print([b(n) for n in range(37)]) # Peter Luschny, Nov 11 2020

Formula

a(n) = (1/(2*n))*Sum_{k=1..n} (sigma[2](k)+sigma[3](k))*a(n-k). - Vladeta Jovovic, Sep 17 2002
a(n) ~ Pi^(1/24) * exp(1/24 - Zeta(3) / (8*Pi^2) + 75*Zeta(3)^3 / (2*Pi^8) - 15^(5/4) * Zeta(3)^2 * n^(1/4) / (2^(7/4)*Pi^5) + 15^(1/2) * Zeta(3) * n^(1/2) / (2^(1/2)*Pi^2) + 2^(7/4) * Pi * n^(3/4) / (3*15^(1/4))) / (A^(1/2) * 2^(157/96) * 15^(13/96) * n^(61/96)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant and Zeta(3) = A002117 = 1.202056903... . - Vaclav Kotesovec, Mar 11 2015
G.f.: exp(Sum_{k>=1} (sigma_2(k) + sigma_3(k))*x^k/(2*k)). - Ilya Gutkovskiy, Aug 21 2018

Extensions

More terms from Sascha Kurz, Aug 15 2002

A096751 Square table, read by antidiagonals, where T(n,k) equals the number of n-dimensional partitions of k.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 3, 3, 1, 1, 1, 4, 6, 5, 1, 1, 1, 5, 10, 13, 7, 1, 1, 1, 6, 15, 26, 24, 11, 1, 1, 1, 7, 21, 45, 59, 48, 15, 1, 1, 1, 8, 28, 71, 120, 140, 86, 22, 1, 1, 1, 9, 36, 105, 216, 326, 307, 160, 30, 1, 1, 1, 10, 45, 148, 357, 657, 835, 684, 282, 42, 1
Offset: 0

Views

Author

Paul D. Hanna, Jul 07 2004

Keywords

Comments

Main diagonal forms A096752. Antidiagonal sums form A096753. Row with index n lists the row sums of the n-th matrix power of triangle A096651, for n>=0.

Examples

			n-th row lists n-dimensional partitions; table begins with n=0:
  [1,1,1,1,1,1,1,1,1,1,1,1,...],
  [1,1,2,3,5,7,11,15,22,30,42,56,...],
  [1,1,3,6,13,24,48,86,160,282,500,859,...],
  [1,1,4,10,26,59,140,307,684,1464,3122,...],
  [1,1,5,15,45,120,326,835,2145,5345,...],
  [1,1,6,21,71,216,657,1907,5507,15522,...],
  [1,1,7,28,105,357,1197,3857,12300,38430,...],
  [1,1,8,36,148,554,2024,7134,24796,84625,...],
  [1,1,9,45,201,819,3231,12321,46209,170370,...],
  [1,1,10,55,265,1165,4927,20155,80920,...],...
Array begins:
      k=0:  k=1:  k=2:  k=3:  k=4:  k=5:  k=6:  k=7:  k=8:
  n=0:  1     1     1     1     1     1     1     1     1
  n=1:  1     1     2     3     5     7    11    15    22
  n=2:  1     1     3     6    13    24    48    86   160
  n=3:  1     1     4    10    26    59   140   307   684
  n=4:  1     1     5    15    45   120   326   835  2145
  n=5:  1     1     6    21    71   216   657  1907  5507
  n=6:  1     1     7    28   105   357  1197  3857 12300
  n=7:  1     1     8    36   148   554  2024  7134 24796
  n=8:  1     1     9    45   201   819  3231 12321 46209
  n=9:  1     1    10    55   265  1165  4927 20155 80920
		

References

  • G. E. Andrews, The Theory of Partitions, Add.-Wes. 1976, pp. 189-197.

Crossrefs

Rows: A000012 (n=0), A000041 (n=1), A000219 (n=2), A000293 (n=3), A000334 (n=4), A000390 (n=5), A000416 (n=6), A000427 (n=7), A179855 (n=8).
Columns: A008778 (k=4), A008779 (k=5), A042984 (k=6).
Cf. A096806.
Cf. A042984.

Programs

  • Mathematica
    trans[x_]:=If[x=={},{},Transpose[x]];
    levptns[n_,k_]:=If[k==1,IntegerPartitions[n],Join@@Table[Select[Tuples[levptns[#,k-1]&/@y],And@@(GreaterEqual@@@trans[Flatten/@(PadRight[#,ConstantArray[n,k-1]]&/@#)])&],{y,IntegerPartitions[n]}]];
    Table[If[sum==k,1,Length[levptns[k,sum-k]]],{sum,0,10},{k,0,sum}] (* Gus Wiseman, Jan 27 2019 *)

Formula

T(0, n)=T(n, 0)=T(n, 1)=1 for n>=0.
Inverse binomial transforms of the columns is given by triangle A096806.
Showing 1-10 of 41 results. Next