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A284607 Expansion of (eta(q^3)eta(q^6)/(eta(q)eta(q^2)))^4 in powers of q. 3
1, 4, 18, 52, 159, 396, 1004, 2260, 5103, 10680, 22260, 44028, 86453, 163424, 306288, 557716, 1006524, 1775844, 3105740, 5333208, 9081243, 15231504, 25343808, 41636124, 67891309, 109500440, 175378446, 278234720, 438540456, 685449000, 1064868020, 1642037524 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..10000

FORMULA

Convolution inverse of A121667.

a(n) ~ exp(2*Pi*sqrt(2*n/3)) / (2^(3/4) * 3^(17/4) * n^(3/4)). - Vaclav Kotesovec, Mar 30 2017

MATHEMATICA

CoefficientList[Series[(QPochhammer[q^3] QPochhammer[q^6]/(QPochhammer[q] QPochhammer[q^2]))^4, {q, 0, 100}], q] (* Indranil Ghosh, Mar 30 2017 *)

PROG

q='q+O('q^66); Vec((eta(q^3)*eta(q^6)/(eta(q)*eta(q^2)))^4) \\ Joerg Arndt, Mar 31 2017

CROSSREFS

Cf. A045484, A121667.

Sequence in context: A300493 A300876 A301486 * A297945 A320544 A020644

Adjacent sequences:  A284604 A284605 A284606 * A284608 A284609 A284610

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Mar 30 2017

STATUS

approved

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Last modified May 26 03:48 EDT 2019. Contains 323579 sequences. (Running on oeis4.)