A022641 Expansion of Product_{m>=1} (1 + m*q^m)^13.

1, 13, 104, 663, 3614, 17576, 78299, 324766, 1269242, 4715204, 16762551, 57327556, 189418658, 606787572, 1890046210, 5738539729, 17019191579, 49394158541, 140507716414, 392299039821, 1076369417474, 2905414115877, 7722941644821, 20233362612424, 52288914446548, 133389316899462

Offset

0,2

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Maple

[seq(coeff(series(mul((1+m*q^m)^(13), m=1..100), q, 101), q, j), j=0..25)]; # Muniru A Asiru, Feb 18 2018

Mathematica

With[{nmax = 50}, CoefficientList[Series[Product[(1 + k*q^k)^13, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Feb 17 2018 *)

Prog

(PARI) m=50; q='q+O('q^m); Vec(prod(n=1, m, (1+n*q^n)^13)) \\ G. C. Greubel, Feb 17 2018
(Magma) Coefficients(&*[(1+m*x^m)^13:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Feb 17 2018

Crossrefs

Column k=13 of A297321.

Sequence in context: A278555 A282921 A023011 * A000590 A052065 A303967

Adjacent sequences: A022638 A022639 A022640 * A022642 A022643 A022644

Keyword

nonn

Author

N. J. A. Sloane

Status

approved