A022643 Expansion of Product_{m>=1} (1 + m*q^m)^15.

1, 15, 135, 950, 5670, 30003, 144680, 647055, 2717760, 10820640, 41128374, 150073470, 528074655, 1798537380, 5947216050, 19142919543, 60113026305, 184513760775, 554517086825, 1634047143090, 4727605374594, 13444544485435, 37620762642885, 103678546403985, 281639925782930

Offset

0,2

Links

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

Maple

[seq(coeff(series(mul((1+m*q^m)^(15), 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)^15, {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)^15)) \\ G. C. Greubel, Feb 17 2018
(Magma) Coefficients(&*[(1+m*x^m)^15:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Feb 17 2018

Crossrefs

Column k=15 of A297321.

Sequence in context: A027629 A023013 A036217 * A125378 A254409 A155648

Adjacent sequences: A022640 A022641 A022642 * A022644 A022645 A022646

Keyword

nonn

Author

N. J. A. Sloane

Status

approved