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A022678 Expansion of Product_{m>=1} (1-m*q^m)^18. 2
1, -18, 117, -222, -936, 4680, -951, -23634, 4815, 89692, 170019, -583992, -1009011, 1753434, 3755619, 3911748, -16001739, -35135352, 6931209, 99524520, 287076168, -92384118, -969330771, -1271547612, -41096046 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..1000

MATHEMATICA

With[{nmax = 50}, CoefficientList[Series[Product[(1 - k*q^k)^18, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Jul 18 2018 *)

PROG

(PARI) m=50; q='q+O('q^m); Vec(prod(n=1, m, (1-n*q^n)^18)) \\ G. C. Greubel, Jul 18 2018

(MAGMA) Coefficients(&*[(1-m*x^m)^18:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Jul 18 2018

CROSSREFS

Sequence in context: A061803 A207103 A101089 * A293878 A044350 A044731

Adjacent sequences:  A022675 A022676 A022677 * A022679 A022680 A022681

KEYWORD

sign

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified December 3 20:56 EST 2020. Contains 338920 sequences. (Running on oeis4.)