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A004406 Expansion of (Sum_{n=-inf..inf} x^(n^2))^(-5). 2
1, -10, 60, -280, 1110, -3912, 12600, -37760, 106620, -286290, 736184, -1822920, 4365800, -10149320, 22971120, -50744448, 109643350, -232145040, 482403060, -985229640, 1980034104, -3920000400, 7652388280, -14742829440 (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 * 5^(3/2)*exp(Pi*sqrt(5*n)) / (512*n^2). - Vaclav Kotesovec, Aug 18 2015

From Ilya Gutkovskiy, Sep 20 2018: (Start)

G.f.: 1/theta_3(x)^5, where theta_3() is the Jacobi theta function.

G.f.: Product_{k>=1} 1/((1 - x^(2*k))*(1 + x^(2*k-1))^2)^5. (End)

MATHEMATICA

nmax = 30; CoefficientList[Series[Product[((1 + (-x)^k)/(1 - (-x)^k))^5, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Aug 18 2015 *)

CROSSREFS

Cf. A000122, A000132.

Sequence in context: A228581 A241929 A278721 * A003472 A112502 A293081

Adjacent sequences:  A004403 A004404 A004405 * A004407 A004408 A004409

KEYWORD

sign

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified June 19 17:16 EDT 2019. Contains 324222 sequences. (Running on oeis4.)