A022691 Expansion of Product_{m>=1} (1-m*q^m)^31.

1, -31, 403, -2666, 7254, 17329, -187488, 384865, 916050, -4785594, 267220, 23607058, 8499735, -138349218, -198872750, 1055690151, 1063384258, -4561862102, -6887455628, 9053067640, 53042071422

Offset: 0

Author

N. J. A. Sloane

Keywords

• sign

Links

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

Programs

Magma

Coefficients(&*[(1-m*x^m)^31:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Jul 19 2018

Mathematica

With[{nmax = 50}, CoefficientList[Series[Product[(1 - k*q^k)^31, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Jul 19 2018 *)

PARI

m=50; q='q+O('q^m); Vec(prod(n=1,m,(1-n*q^n)^31)) \\ G. C. Greubel, Jul 19 2018