OFFSET
0,3
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..500
PROG
(PARI) m = 30; Vec(prod(k=1, m, 1 + x^k + 2*x^(2*k) + 3*x^(3*k)) + O(x^m)) \\ Michel Marcus, Oct 07 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Oct 06 2017
STATUS
approved