A022623 Expansion of Product_{m>=1} (1+q^m)^(-28).

1, -28, 378, -3304, 21259, -108892, 469630, -1778536, 6096125, -19303088, 57249374, -160633424, 429762354, -1103189388, 2730461208, -6542033848, 15223719392, -34504452668, 76349114366, -165267288816, 350579820199, -729912979244, 1493568080228, -3007227042624, 5964244118126

Offset: 0

Author

N. J. A. Sloane

Keywords

• sign

Links

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

Programs

Mathematica

nmax = 50; CoefficientList[Series[Product[1/(1 + x^k)^28, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Aug 27 2015 *)

Formula

a(n) ~ (-1)^n * 7^(1/4) * exp(Pi*sqrt(14*n/3)) / (2 * 6^(1/4) * n^(3/4)). - Vaclav Kotesovec, Aug 27 2015