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%I #13 Jun 22 2017 08:40:40
%S 1,-46,1104,-18400,239154,-2581152,24056160,-198823040,1485433104,
%T -10177345486,64663512288,-384402300960,2153523131040,-11437761254432,
%U 57880610587200,-280265903825280,1303272560982834,-5838468742907712
%N Expansion of (Sum_{n=-inf..inf} x^(n^2))^(-23).
%H Seiichi Manyama, <a href="/A004424/b004424.txt">Table of n, a(n) for n = 0..10000</a>
%F a(n) ~ (-1)^n * exp(Pi*sqrt(m*n)) * m^((m+1)/4) / (2^(3*(m+1)/2) * n^((m+3)/4)), set m = 23 for this sequence. - _Vaclav Kotesovec_, Aug 18 2015
%t nmax = 30; CoefficientList[Series[Product[((1 + (-x)^k)/(1 - (-x)^k))^23, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Aug 18 2015 *)
%K sign
%O 0,2
%A _N. J. A. Sloane_