A004423 Expansion of (Sum_{n=-inf..inf} x^(n^2))^(-22).

1, -44, 1012, -16192, 202356, -2102936, 18896064, -150747520, 1088265332, -7211641580, 44356933544, -255472920256, 1387689358528, -7151069205016, 35134409940608, -165273439140480, 747047401948276, -3254796172584792

Offset

0,2

Links

Seiichi Manyama, Table of n, a(n) for n = 0..10000

Formula

a(n) ~ (-1)^n * exp(Pi*sqrt(m*n)) * m^((m+1)/4) / (2^(3*(m+1)/2) * n^((m+3)/4)), set m = 22 for this sequence. - Vaclav Kotesovec, Aug 18 2015

Mathematica

nmax = 30; CoefficientList[Series[Product[((1 + (-x)^k)/(1 - (-x)^k))^22, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Aug 18 2015 *)

Crossrefs

Sequence in context: A010996 A295251 A295650 * A238601 A172978 A345410

Adjacent sequences: A004420 A004421 A004422 * A004424 A004425 A004426

Keyword

sign

Author

N. J. A. Sloane

Status

approved