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A004419 Expansion of (Sum_{n=-inf..inf} x^(n^2))^(-18). 1
1, -36, 684, -9120, 95724, -841320, 6433248, -43918272, 272670444, -1561033348, 8329222584, -41772509280, 198265106400, -895619289384, 3868763174208, -16044584545344, 64103055405804, -247461482137032 (list; graph; refs; listen; history; text; internal format)
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 = 18 for this sequence. - Vaclav Kotesovec, Aug 18 2015

MATHEMATICA

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

CROSSREFS

Sequence in context: A239181 A053947 A157092 * A268900 A185491 A220758

Adjacent sequences:  A004416 A004417 A004418 * A004420 A004421 A004422

KEYWORD

sign

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified September 20 11:47 EDT 2021. Contains 347584 sequences. (Running on oeis4.)