OFFSET
0,2
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..10000
FORMULA
Self-convolution of A022629. - Alois P. Heinz, Dec 28 2017
G.f.: exp(2*Sum_{j>=1} Sum_{k>=1} (-1)^(j+1)*k^j*x^(j*k)/j). - Ilya Gutkovskiy, Feb 08 2018
MATHEMATICA
nn=34; CoefficientList [Series[ Product[(1 + m*q^m)^2, {m, nn}], {q, 0, nn}], q] (* Robert G. Wilson v, Feb 08 2018 *)
PROG
(PARI) m=50; q='q+O('q^m); Vec(prod(n=1, m, (1+n*q^n)^2)) \\ G. C. Greubel, Feb 16 2018
(Magma) Coefficients(&*[(1+m*x^m)^2:m in [1..40]])[1..40] where x is PolynomialRing(Integers()).1; // G. C. Greubel, Feb 16 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved