OFFSET
0,2
FORMULA
a(n) ~ 2 * n^(2*n).
MATHEMATICA
Table[SeriesCoefficient[Product[(1 + n^(k + 1)*x^k)/(1 - n^(k + 1)*x^k), {k, 1, n}], {x, 0, n}], {n, 0, 20}]
Table[SeriesCoefficient[2*x + ((1 - n)*QPochhammer[-n, n*x, 1 + n]) / ((1 + n)*QPochhammer[n, n*x, 1 + n]), {x, 0, n}], {n, 0, 20}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Jul 19 2021
STATUS
approved