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A258941 Convolution inverse of A058537. 4
1, -7, 41, -253, 1555, -9532, 58463, -358600, 2199546, -13491360, 82752059, -507576937, 3113328401, -19096245457, 117130782240, -718445946527, 4406737223117, -27029636742811, 165791883077354, -1016918901125280, 6237482995373629, -38258895644996020 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 0..1260

FORMULA

a(n) ~ (-1)^n * c * exp(Pi*n/sqrt(3)), where c = A258942 = 8*exp(Pi/(6*sqrt(3))) * Pi^(5/2) / Gamma(1/6)^3 =  1.09786330972731096865822482325074133091288... . - Vaclav Kotesovec, Nov 14 2015

Expansion of q^(-1/6)* eta[q]*eta[q^9]^2/(eta[q]^3 + 9*eta[q^9]^3) in powers of q. - G. C. Greubel, Jun 22 2018

MATHEMATICA

CoefficientList[Series[QPochhammer[x, x] * QPochhammer[x^3, x^3]^2 / (QPochhammer[x, x]^3 + 9*x*QPochhammer[x^9, x^9]^3), {x, 0, 50}], x]

eta[q_]:= q^(1/24)*QPochhammer[q]; CoefficientList[Series[q^(-1/6)* eta[q]*eta[q^9]^2/(eta[q]^3 + 9*eta[q^9]^3), {q, 0, 60}], q] (* G. C. Greubel, Jun 22 2018 *)

PROG

(PARI) q='q+O('q^50); A = eta(q)*eta(q^3)^2/(eta(q)^3 + 9*q*eta(q^9)^3); Vec(A) \\ G. C. Greubel, Jun 22 2018

CROSSREFS

Cf. A058537, A051273, A058092, A115784, A258942.

Sequence in context: A108983 A115137 A036730 * A080047 A297671 A125120

Adjacent sequences:  A258938 A258939 A258940 * A258942 A258943 A258944

KEYWORD

sign

AUTHOR

Vaclav Kotesovec, Nov 07 2015

STATUS

approved

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Last modified July 24 03:01 EDT 2019. Contains 325290 sequences. (Running on oeis4.)