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 17 results. Next

A257673 Triangle T(n,k), n>=0, 0<=k<=n, read by rows: row n is the inverse binomial transform of the n-th row of array A255961, which has the Euler transform of (j->j*k) in column k.

Original entry on oeis.org

1, 0, 1, 0, 3, 1, 0, 6, 6, 1, 0, 13, 21, 9, 1, 0, 24, 62, 45, 12, 1, 0, 48, 162, 174, 78, 15, 1, 0, 86, 396, 576, 376, 120, 18, 1, 0, 160, 917, 1719, 1509, 695, 171, 21, 1, 0, 282, 2036, 4761, 5340, 3285, 1158, 231, 24, 1, 0, 500, 4380, 12441, 17234, 13473, 6309, 1792, 300, 27, 1
Offset: 0

Views

Author

Alois P. Heinz, May 03 2015

Keywords

Comments

T is the convolution triangle of the number of plane partitions (A000219). - Peter Luschny, Oct 19 2022

Examples

			Triangle T(n,k) begins:
  1;
  0,   1;
  0,   3,    1;
  0,   6,    6,    1;
  0,  13,   21,    9,    1;
  0,  24,   62,   45,   12,    1;
  0,  48,  162,  174,   78,   15,    1;
  0,  86,  396,  576,  376,  120,   18,   1;
  0, 160,  917, 1719, 1509,  695,  171,  21,  1;
  0, 282, 2036, 4761, 5340, 3285, 1158, 231, 24, 1;
  ...
		

Crossrefs

Columns k=0-10 give: A000007, A000219 (for n>0), A321947, A321948, A321949, A321950, A321951, A321952, A321953, A321954, A321955.
Main diagonal and lower diagonals give: A000012, A008585, A081266.
Row sums give A257674.
T(2n,n) give A257675.
Cf. A255961.

Programs

  • Maple
    A:= proc(n, k) option remember; `if`(n=0, 1, k*add(
          A(n-j, k)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    T:= (n, k)-> add(A(n, k-i)*(-1)^i*binomial(k, i), i=0..k):
    seq(seq(T(n, k), k=0..n), n=0..12);
    # Uses function PMatrix from A357368.
    PMatrix(10, A000219); # Peter Luschny, Oct 19 2022
  • Mathematica
    A[n_, k_] := A[n, k] = If[n==0, 1, k*Sum[A[n-j, k]*DivisorSigma[2, j], {j, 1, n}]/n];
    T[n_, k_] := Sum[A[n, k-i]*(-1)^i*Binomial[k, i], {i, 0, k}];
    Table[T[n, k], {n, 0, 12}, {k, 0, n}] // Flatten (* Jean-François Alcover, Mar 21 2017, translated from Maple *)

Formula

T(n,k) = Sum_{i=0..k} (-1)^i * C(k,i) * A255961(n,k-i).
G.f. of column k: (-1 + Product_{j>=1} 1 / (1 - x^j)^j)^k.

A055998 a(n) = n*(n+5)/2.

Original entry on oeis.org

0, 3, 7, 12, 18, 25, 33, 42, 52, 63, 75, 88, 102, 117, 133, 150, 168, 187, 207, 228, 250, 273, 297, 322, 348, 375, 403, 432, 462, 493, 525, 558, 592, 627, 663, 700, 738, 777, 817, 858, 900, 943, 987, 1032, 1078, 1125, 1173, 1222, 1272
Offset: 0

Views

Author

Barry E. Williams, Jun 14 2000

Keywords

Comments

If X is an n-set and Y a fixed (n-3)-subset of X then a(n-3) is equal to the number of 2-subsets of X intersecting Y. - Milan Janjic, Aug 15 2007
Bisection of A165157. - Jaroslav Krizek, Sep 05 2009
a(n) is the number of (w,x,y) having all terms in {0,...,n} and w=x+y-1. - Clark Kimberling, Jun 02 2012
Numbers m >= 0 such that 8m+25 is a square. - Bruce J. Nicholson, Jul 26 2017
a(n-1) = 3*(n-1) + (n-1)*(n-2)/2 is the number of connected, loopless, non-oriented, multi-edge vertex-labeled graphs with n edges and 3 vertices. Labeled multigraph analog of A253186. There are 3*(n-1) graphs with the 3 vertices on a chain (3 ways to label the middle graph, n-1 ways to pack edges on one of connections) and binomial(n-1,2) triangular graphs (one way to label the graphs, pack 1 or 2 or ...n-2 on the 1-2 edge, ...). - R. J. Mathar, Aug 10 2017
a(n) is also the number of vertices of the quiver for PGL_{n+1} (see Shen). - Stefano Spezia, Mar 24 2020
Starting from a(2) = 7, this is the 4th column of the array: natural numbers written by antidiagonals downwards. See the illustration by Kival Ngaokrajang and the cross-references. - Andrey Zabolotskiy, Dec 21 2021

References

  • Albert H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, p. 193.

Crossrefs

a(n) = A095660(n+1, 2): third column of (1, 3)-Pascal triangle.
Row n=2 of A255961.

Programs

Formula

G.f.: x*(3-2*x)/(1-x)^3.
a(n) = A027379(n), n > 0.
a(n) = A126890(n,2) for n > 1. - Reinhard Zumkeller, Dec 30 2006
a(n) = A000217(n) + A005843(n). - Reinhard Zumkeller, Sep 24 2008
If we define f(n,i,m) = Sum_{k=0..n-i} binomial(n,k)*Stirling1(n-k,i)*Product_{j=0..k-1} (-m-j), then a(n) = -f(n,n-1,3), for n >= 1. - Milan Janjic, Dec 20 2008
a(n) = A167544(n+8). - Philippe Deléham, Nov 25 2009
a(n) = a(n-1) + n + 2 with a(0)=0. - Vincenzo Librandi, Aug 07 2010
a(n) = Sum_{k=1..n} (k+2). - Gary Detlefs, Aug 10 2010
a(n) = A034856(n+1) - 1 = A000217(n+2) - 3. - Jaroslav Krizek, Sep 05 2009
Sum_{n>=1} 1/a(n) = 137/150. - R. J. Mathar, Jul 14 2012
a(n) = 3*n + A000217(n-1) = 3*n - floor(n/2) + floor(n^2/2). - Wesley Ivan Hurt, Jun 15 2013
a(n) = Sum_{i=3..n+2} i. - Wesley Ivan Hurt, Jun 28 2013
a(n) = 3*A000217(n) - 2*A000217(n-1). - Bruno Berselli, Dec 17 2014
a(n) = A046691(n) + 1. Also, a(n) = A052905(n-1) + 2 = A055999(n-1) + 3 for n>0. - Andrey Zabolotskiy, May 18 2016
E.g.f.: x*(6+x)*exp(x)/2. - G. C. Greubel, Apr 05 2019
Sum_{n>=1} (-1)^(n+1)/a(n) = 4*log(2)/5 - 47/150. - Amiram Eldar, Jan 10 2021
From Amiram Eldar, Feb 12 2024: (Start)
Product_{n>=1} (1 - 1/a(n)) = -5*cos(sqrt(33)*Pi/2)/(4*Pi).
Product_{n>=1} (1 + 1/a(n)) = 15*cos(sqrt(17)*Pi/2)/(2*Pi). (End)

A144064 Square array A(n,k), n>=0, k>=0, read by antidiagonals, where column k is Euler transform of (j->k).

Original entry on oeis.org

1, 1, 0, 1, 1, 0, 1, 2, 2, 0, 1, 3, 5, 3, 0, 1, 4, 9, 10, 5, 0, 1, 5, 14, 22, 20, 7, 0, 1, 6, 20, 40, 51, 36, 11, 0, 1, 7, 27, 65, 105, 108, 65, 15, 0, 1, 8, 35, 98, 190, 252, 221, 110, 22, 0, 1, 9, 44, 140, 315, 506, 574, 429, 185, 30, 0, 1, 10, 54, 192, 490, 918, 1265, 1240, 810, 300, 42, 0
Offset: 0

Views

Author

Alois P. Heinz, Sep 09 2008

Keywords

Comments

A(n,k) is also the number of partitions of n into parts of k kinds.
In general, column k > 0 is asymptotic to k^((k+1)/4) * exp(Pi*sqrt(2*k*n/3)) / (2^((3*k+5)/4) * 3^((k+1)/4) * n^((k+3)/4)) * (1 - (Pi*k^(3/2)/(24*sqrt(6)) + sqrt(3)*(k+1)*(k+3)/(8*Pi*sqrt(2*k))) / sqrt(n)). - Vaclav Kotesovec, Feb 28 2015, extended Jan 16 2017
When k is a prime power greater than 1, A(n,k) is the number of conjugacy classes of n X n matrices over a field with k elements that contain an upper-triangular matrix. - Geoffrey Critzer, Nov 11 2022

Examples

			Square array begins:
  1,   1,   1,   1,   1,   1, ...
  0,   1,   2,   3,   4,   5, ...
  0,   2,   5,   9,  14,  20, ...
  0,   3,  10,  22,  40,  65, ...
  0,   5,  20,  51, 105, 190, ...
  0,   7,  36, 108, 252, 506, ...
		

Crossrefs

Cf. A082556 (k=30), A082557 (k=32), A082558 (k=48), A082559 (k=64).
Rows n=0-4 give: A000012, A001477, A000096, A006503, A006504.
Main diagonal gives A008485.
Antidiagonal sums give A067687.

Programs

  • Julia
    # DedekindEta is defined in A000594.
    A144064Column(k, len) = DedekindEta(len, -k)
    for n in 0:8 A144064Column(n, 6) |> println end # Peter Luschny, Mar 10 2018
    
  • Maple
    with(numtheory): etr:= proc(p) local b; b:= proc(n) option remember; `if`(n=0, 1, add(add(d*p(d), d=divisors(j)) *b(n-j), j=1..n)/n) end end: A:= (n,k)-> etr(j->k)(n): seq(seq(A(n, d-n), n=0..d), d=0..14);
  • Mathematica
    a[0, ] = 1; a[, 0] = 0; a[n_, k_] := SeriesCoefficient[ Product[1/(1 - x^j)^k, {j, 1, n}], {x, 0, n}]; Table[a[n - k, k], {n, 0, 11}, {k, n, 0, -1}] // Flatten (* Jean-François Alcover, Dec 06 2013 *)
    etr[p_] := Module[{b}, b[n_] := b[n] = If[n==0, 1, Sum[Sum[d*p[d], {d, Divisors[j]} ]*b[n-j], {j, 1, n}]/n]; b]; A[n_, k_] := etr[k&][n]; Table[A[n, d-n], {d, 0, 14}, {n, 0, d}] // Flatten (* Jean-François Alcover, Mar 30 2015, after Alois P. Heinz *)
  • PARI
    Mat(apply( {A144064_col(k,nMax=9)=Col(1/eta('x+O('x^nMax))^k,nMax)}, [0..9])) \\ M. F. Hasler, Aug 04 2024

Formula

G.f. of column k: Product_{j>=1} 1/(1-x^j)^k.
A(n,k) = Sum_{i=0..k} binomial(k,i) * A060642(n,k-i):

A161870 Convolution square of A000219.

Original entry on oeis.org

1, 2, 7, 18, 47, 110, 258, 568, 1237, 2600, 5380, 10870, 21652, 42350, 81778, 155676, 292964, 544846, 1003078, 1828128, 3301952, 5911740, 10499385, 18502582, 32371011, 56240816, 97073055, 166497412, 283870383, 481212656, 811287037, 1360575284, 2270274785, 3769835178, 6230705170, 10251665550, 16794445441
Offset: 0

Views

Author

Gary W. Adamson, Jun 20 2009

Keywords

Comments

Equals [1,2,3,...] * [1,0,4,0,10,0,20,...] * [1,0,0,6,0,0,21,...] * [1,0,0,0,8,0,0,0,36,...] * ... - Gary W. Adamson, Jul 06 2009
Number of pairs of planar partitions of u and v where u + v = n. - Joerg Arndt, Apr 22 2014

Crossrefs

Cf. A000219.
Column k=2 of A255961.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, 2*add(
          a(n-j)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Mar 12 2015
  • Mathematica
    nn = 36; CoefficientList[Series[Product[1/(1 - x^i)^(2 i), {i, 1, nn}] , {x, 0, nn}], x] (* Geoffrey Critzer, Nov 29 2014 *)
  • PARI
    N=66;x='x+O('x^N); Vec(1/prod(k=1,N,(1-x^k)^k)^2) \\ Joerg Arndt, Apr 22 2014

Formula

G.f.: 1 / prod(k>=1, (1-x^k)^k )^2. - Joerg Arndt, Apr 22 2014
a(n) ~ Zeta(3)^(2/9) * exp(1/6 + 3*n^(2/3)*(Zeta(3)/2)^(1/3)) / (A^2 * 2^(1/18) * sqrt(3*Pi) * n^(13/18)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant and Zeta(3) = A002117 = 1.202056903... . - Vaclav Kotesovec, Feb 27 2015
G.f.: exp(2*Sum_{k>=1} x^k/(k*(1 - x^k)^2)). - Ilya Gutkovskiy, May 29 2018

Extensions

Added more terms, Joerg Arndt, Apr 22 2014

A255672 Coefficient of x^n in Product_{k>=1} 1/(1-x^k)^(k*n).

Original entry on oeis.org

1, 1, 7, 37, 215, 1251, 7459, 44885, 272727, 1668313, 10263057, 63423482, 393440867, 2448542136, 15280435191, 95588065737, 599213418327, 3763242239317, 23673166664695, 149138199543613, 940796936557265, 5941862248557566, 37568309060087582, 237767215209245583
Offset: 0

Views

Author

Vaclav Kotesovec, Mar 01 2015

Keywords

Comments

Number of partitions of n when parts i are of n*i kinds. - Alois P. Heinz, Nov 23 2018
From Peter Bala, Apr 18 2023: (Start)
The Gauss congruences a(n*p^k) == a(n*p^(k-1)) (mod p^k) hold for all primes p and all positive integers n and k.
Conjecture: the stronger supercongruences a(n*p^k) == a(n*p^(k-1)) (mod p^(2*k)) hold for all primes p >= 3 and all positive integers n and k. (End)

Crossrefs

Main diagonal of A255961.

Programs

  • Maple
    b:= proc(n, k) option remember; `if`(n=0, 1, k*add(
          b(n-j, k)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    a:= n-> b(n$2):
    seq(a(n), n=0..30);  # Alois P. Heinz, Mar 11 2015
  • Mathematica
    Table[SeriesCoefficient[Product[1/(1-x^k)^(k*n),{k,1,n}],{x,0,n}], {n,0,20}] (* Vaclav Kotesovec, Mar 01 2015 *)

Formula

a(n) ~ c * d^n / sqrt(n), where d = 6.468409145117839606941857350154192468889057616577..., c = 0.25864792865819067933968646380369970564... . - Vaclav Kotesovec, Mar 01 2015
a(n) = [x^n] exp(n*Sum_{k>=1} x^k/(k*(1 - x^k)^2)). - Ilya Gutkovskiy, May 30 2018

A255610 G.f.: Product_{k>=1} 1/(1-x^k)^(3*k).

Original entry on oeis.org

1, 3, 12, 37, 111, 303, 804, 2022, 4950, 11715, 27081, 61083, 135112, 293142, 625620, 1314267, 2722323, 5564172, 11234865, 22424904, 44284545, 86573147, 167648418, 321746907, 612274678, 1155782109, 2165116416, 4026391221, 7435806048, 13641093684, 24865920932
Offset: 0

Views

Author

Vaclav Kotesovec, Feb 28 2015

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, 3*add(
          a(n-j)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Mar 11 2015
  • Mathematica
    nmax=50; CoefficientList[Series[Product[1/(1-x^k)^(3*k),{k,1,nmax}],{x,0,nmax}],x]

Formula

G.f.: Product_{k>=1} 1/(1-x^k)^(3*k).
a(n) ~ Zeta(3)^(1/4) * exp(1/4 + 2^(-2/3) * 3^(4/3) * Zeta(3)^(1/3) * n^(2/3)) / (A^3 * 6^(1/4) * sqrt(Pi) * n^(3/4)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant and Zeta(3) = A002117 = 1.202056903... . - Vaclav Kotesovec, Feb 28 2015
More precise asymptotics: a(n) ~ Zeta(3)^(1/4) * exp(1/4 + 2^(-2/3) * 3^(4/3) * Zeta(3)^(1/3) * n^(2/3)) / (A^3 * 6^(1/4) * sqrt(Pi) * n^(3/4)) * (1 - c/n^(2/3)), where c = 0.21774822... . - Vaclav Kotesovec, Oct 15 2015
G.f.: exp(3*Sum_{k>=1} x^k/(k*(1 - x^k)^2)). - Ilya Gutkovskiy, May 29 2018

Extensions

New name from Vaclav Kotesovec, Mar 12 2015

A299166 Expansion of 1/(1 - x*Product_{k>=1} 1/(1 - x^k)^k).

Original entry on oeis.org

1, 1, 2, 6, 17, 48, 132, 365, 1003, 2759, 7583, 20843, 57283, 157442, 432719, 1189317, 3268818, 8984318, 24693343, 67869557, 186539251, 512702559, 1409161449, 3873076007, 10645137706, 29258128633, 80415877302, 221022792843, 607480469466, 1669658209311, 4589050472041
Offset: 0

Views

Author

Ilya Gutkovskiy, Feb 04 2018

Keywords

Crossrefs

Antidiagonal sums of A255961.

Programs

  • Maple
    b:= proc(n, k) option remember; `if`(n=0, 1, k*add(
           b(n-j, k)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    a:= n-> add(b(n-j, j), j=0..n):
    seq(a(n), n=0..35);  # Alois P. Heinz, Feb 04 2018
  • Mathematica
    nmax = 30; CoefficientList[Series[1/(1 - x Product[1/(1 - x^k)^k, {k, 1, nmax}]), {x, 0, nmax}], x]

Formula

G.f.: 1/(1 - x*Product_{k>=1} 1/(1 - x^k)^k).
a(0) = 1; a(n) = Sum_{k=1..n} A000219(k-1)*a(n-k).

A193427 G.f.: Product_{k>=1} 1/(1-x^k)^(8*k).

Original entry on oeis.org

1, 8, 52, 272, 1266, 5344, 20992, 77584, 272727, 917936, 2975492, 9328736, 28391410, 84122688, 243265848, 688008048, 1906476351, 5184024112, 13851270944, 36409640400, 94255399886, 240529147072, 605574003464, 1505340071744
Offset: 0

Views

Author

Martin Y. Veillette, Jul 28 2011

Keywords

Comments

Previous name was: Number of plane partitions of n into parts of 8 kinds.
In general, if g.f. = Product_{k>=1} 1/(1-x^k)^(m*k) and m > 0, then a(n) ~ 2^(m/36 - 1/3) * exp(m/12 + 3 * 2^(-2/3) * m^(1/3) * zeta(3)^(1/3) * n^(2/3)) * (m*zeta(3))^(m/36 + 1/6) / (A^m * sqrt(3*Pi) * n^(m/36 + 2/3)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant. - Vaclav Kotesovec, Mar 01 2015

Crossrefs

Cf. A000219 (m=1), A161870 (m=2), A255610 (m=3), A255611 (m=4), A255612 (m=5), A255613 (m=6), A255614 (m=7).
Column k=8 of A255961.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, 8*add(
          a(n-j)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Mar 11 2015
  • Mathematica
    ANS = Block[{kmax = 50},
      Coefficient[
       Series[Product[1/(1 - x^k)^(8 k), {k, 1, kmax}], {x, 0, kmax}], x,
       Range[0, kmax]]]
    (* Second program: *)
    a[n_] := a[n] = If[n==0, 1, 8*Sum[a[n-j]*DivisorSigma[2, j], {j, 1, n}]/n]; Table[a[n], {n, 0, 30}] (* Jean-François Alcover, Feb 07 2017, after Alois P. Heinz *)
  • PARI
    Vec(prod(k=1,100\2,(1-x^k)^(-8*k),1+O(x^101))) \\ Charles R Greathouse IV, Aug 09 2011

Formula

G.f.: Product_{k>=1} (1-x^k)^(-8*k).
a(n) ~ 2^(19/18) * zeta(3)^(7/18) * exp(2/3 + 3 * 2^(1/3) * zeta(3)^(1/3) * n^(2/3)) / (A^8 * sqrt(3*Pi) * n^(8/9)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant and zeta(3) = A002117 = 1.202056903... . - Vaclav Kotesovec, Feb 28 2015
G.f.: exp(8*Sum_{k>=1} x^k/(k*(1 - x^k)^2)). - Ilya Gutkovskiy, May 29 2018
Euler transform of 8*k. - Georg Fischer, Aug 15 2020

Extensions

New name from Vaclav Kotesovec, Mar 12 2015

A255611 G.f.: Product_{k>=1} 1/(1-x^k)^(4*k).

Original entry on oeis.org

1, 4, 18, 64, 215, 660, 1938, 5400, 14527, 37728, 95278, 234344, 563506, 1326796, 3066040, 6963048, 15564661, 34282360, 74486376, 159785472, 338703796, 709957616, 1472529670, 3023894672, 6151408852, 12402137024, 24792822174, 49162962280, 96737562642
Offset: 0

Views

Author

Vaclav Kotesovec, Feb 28 2015

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, 4*add(
          a(n-j)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Mar 11 2015
  • Mathematica
    nmax=50; CoefficientList[Series[Product[1/(1-x^k)^(4*k),{k,1,nmax}],{x,0,nmax}],x]

Formula

G.f.: Product_{k>=1} 1/(1-x^k)^(4*k).
a(n) ~ 2^(1/3) * Zeta(3)^(5/18) * exp(1/3 + 3 * Zeta(3)^(1/3) * n^(2/3)) / (A^4 * sqrt(3*Pi) * n^(7/9)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant and Zeta(3) = A002117 = 1.202056903... . - Vaclav Kotesovec, Feb 28 2015
G.f.: exp(4*Sum_{k>=1} x^k/(k*(1 - x^k)^2)). - Ilya Gutkovskiy, May 29 2018

Extensions

New name from Vaclav Kotesovec, Mar 12 2015

A255612 G.f.: Product_{k>=1} 1/(1-x^k)^(5*k).

Original entry on oeis.org

1, 5, 25, 100, 370, 1251, 4005, 12150, 35400, 99365, 270353, 715025, 1844650, 4652075, 11494605, 27872056, 66428295, 155809600, 360079225, 820715820, 1846583863, 4104572975, 9019869125, 19608423750, 42193733645, 89917531549, 189863358445, 397401303850
Offset: 0

Views

Author

Vaclav Kotesovec, Feb 28 2015

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, 5*add(
          a(n-j)*numtheory[sigma][2](j), j=1..n)/n)
        end:
    seq(a(n), n=0..30);  # Alois P. Heinz, Mar 11 2015
  • Mathematica
    nmax=50; CoefficientList[Series[Product[1/(1-x^k)^(5*k),{k,1,nmax}],{x,0,nmax}],x]

Formula

G.f.: Product_{k>=1} 1/(1-x^k)^(5*k).
a(n) ~ 5^(11/36) * Zeta(3)^(11/36) * exp(5/12 + 3 * 2^(-2/3) * 5^(1/3) * Zeta(3)^(1/3) * n^(2/3)) / (A^5 * 2^(7/36) * sqrt(3*Pi) * n^(29/36)), where A = A074962 = 1.2824271291... is the Glaisher-Kinkelin constant and Zeta(3) = A002117 = 1.202056903... . - Vaclav Kotesovec, Feb 28 2015
G.f.: exp(5*Sum_{k>=1} x^k/(k*(1 - x^k)^2)). - Ilya Gutkovskiy, May 29 2018

Extensions

New name from Vaclav Kotesovec, Mar 12 2015
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