OFFSET
0,4
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..10000
MATHEMATICA
nmax = 50; CoefficientList[Series[Product[(1-k*x^k)/(1-x^k), {k, 1, nmax}], {x, 0, nmax}], x]
CROSSREFS
KEYWORD
sign
AUTHOR
Vaclav Kotesovec, Jan 08 2016
STATUS
approved