A022705 Expansion of Product_{m>=1} (1+m*q^m)^-13.

1, -13, 65, -156, 273, -1014, 3497, -6539, 12116, -39819, 99086, -178009, 395044, -988651, 2103335, -4237363, 8806967, -19098131, 40962220, -80207062, 158661230, -337459980, 681006807, -1307462312, 2595164702

Offset: 0

Author

N. J. A. Sloane

Keywords

• sign

Links

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

Programs

Mathematica

With[{nmax = 50}, CoefficientList[Series[Product[(1 + k*q^k)^-13, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Jul 20 2018 *)

PARI

m=50; q='q+O('q^m); Vec(prod(n=1,m,(1+n*q^n)^-13)) \\ G. C. Greubel, Jul 20 2018