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A022687
Expansion of Product_{m>=1} (1-m*q^m)^27.
2
1, -27, 297, -1548, 2079, 18036, -88893, 42471, 632259, -1042392, -2491695, 3171771, 19897479, -6178491, -149788494, 40753548, 598051971, 397032246, -1758684468, -5331986973, 4009289778, 22014953235
OFFSET
0,2
LINKS
MATHEMATICA
With[{nmax = 50}, CoefficientList[Series[Product[(1 - k*q^k)^27, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Jul 19 2018 *)
PROG
(PARI) m=50; q='q+O('q^m); Vec(prod(n=1, m, (1-n*q^n)^27)) \\ G. C. Greubel, Jul 19 2018
(Magma) Coefficients(&*[(1-m*x^m)^27:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Jul 19 2018
CROSSREFS
Sequence in context: A049011 A115246 A202126 * A083813 A086574 A274832
KEYWORD
sign
STATUS
approved