OFFSET
0,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..386
FORMULA
a(n) ~ 2*n^n * (1 + 2*exp(-1)/n + (exp(-1) + 10*exp(-2))/n^2). - Vaclav Kotesovec, Sep 16 2017
MATHEMATICA
nmax = 20; CoefficientList[Series[Product[(1 + k^k*x^k)/(1 - k^k*x^k), {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Sep 16 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 15 2017
STATUS
approved