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A304460
Coefficient of x^n in Product_{k>=1} 1/(1-x^k)^(n^3).
2
1, 1, 44, 4410, 905840, 318906400, 172185088824, 132357574570221, 137406570363495360, 185242628827767255255, 314645673306845990409300, 657405676947400829561901359, 1656968286301847988118098735168, 4957425610652588047512198547937050
OFFSET
0,3
COMMENTS
In general, for m>=3, coefficient of x^n in Product_{k>=1} 1/(1-x^k)^(n^m) is asymptotic to n^(m*n)/n!.
FORMULA
a(n) ~ exp(n) * n^(2*n - 1/2) / sqrt(2*Pi).
MATHEMATICA
nmax = 20; Table[SeriesCoefficient[Product[1/(1-x^k)^(n^3), {k, 1, n}], {x, 0, n}], {n, 0, nmax}]
nmax = 20; Table[SeriesCoefficient[1/QPochhammer[x]^(n^3), {x, 0, n}], {n, 0, nmax}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, May 13 2018
STATUS
approved