OFFSET
0,9
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..1000
FORMULA
G.f.: exp(Sum_{k>=1} x^k * Sum_{d|k} (1 - x)^d/d). - Ilya Gutkovskiy, Apr 16 2019
MATHEMATICA
m = 49; CoefficientList[Series[Product[1/(1 - x^k * (1 - x)), {k, 1, m}], {x, 0, m}], x] (* Amiram Eldar, May 14 2021 *)
PROG
(PARI) N=66; x='x+O('x^N); Vec(1/prod(k=1, N, 1-x^k*(1-x)))
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Apr 16 2019
STATUS
approved