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A122268 Expansion of f(-q)^2*Q(q)^2 in powers of q. 0
1, 478, 60959, 925922, 5764801, 20722082, 54717118, 103864320, 173379838, 194669278, 214358881, 0, -92574720, -799067998, -815502237, -1959423842, -1300569598, -2939811840, 0, -2686875362, 3317297278, 0, 8406236160, 1662767518 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

f(-q) (g.f. A010815) and Q(q) (g.f. A004009) are Ramanujan q-series.

PROG

(PARI) {a(n)=local(A); if(n<0, 0, A=x*O(x^n); polcoeff( eta(x+A)^2*sum(k=1, n, 240*sigma(k, 3)*x^k, 1+A)^2, n))}

CROSSREFS

Sequence in context: A020375 A031788 A119129 * A186950 A056987 A025025

Adjacent sequences:  A122265 A122266 A122267 * A122269 A122270 A122271

KEYWORD

sign

AUTHOR

Michael Somos, Aug 28 2006

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Last modified February 14 20:38 EST 2012. Contains 205663 sequences.