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A022647
Expansion of Product_{m>=1} (1 + m*q^m)^19.
2
1, 19, 209, 1748, 12217, 74898, 414865, 2116885, 10087480, 45348041, 193814402, 792340831, 3113639744, 11808753973, 43368768307, 154674601937, 537009888061, 1818759910067, 6019901796578, 19503777943838, 61940839239196, 193067981970548, 591298084019937
OFFSET
0,2
LINKS
MAPLE
[seq(coeff(series(mul((1+m*q^m)^(19), m=1..100), q, 101), q, j), j=0..25)]; # Muniru A Asiru, Feb 18 2018
MATHEMATICA
With[{nmax = 50}, CoefficientList[Series[Product[(1 + k*q^k)^19, {k, 1, nmax}], {q, 0, nmax}], q]] (* G. C. Greubel, Feb 17 2018 *)
PROG
(PARI) m=50; q='q+O('q^m); Vec(prod(n=1, m, (1+n*q^n)^19)) \\ G. C. Greubel, Feb 17 2018
(Magma) Coefficients(&*[(1+m*x^m)^19:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Feb 17 2018
CROSSREFS
Column k=19 of A297321.
Sequence in context: A289423 A278556 A023017 * A032613 A199132 A201791
KEYWORD
nonn
STATUS
approved