OFFSET
0,3
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..1000
FORMULA
a(n) ~ exp(2^(5/2) * Pi * (127*Zeta(7)/15)^(1/8) * n^(7/8)/7 - Pi * (5/(127*Zeta(7)))^(1/8) * n^(1/8) / (504 * sqrt(2) * 3^(7/8))) * (127*Zeta(7)/15)^(1/16) / (2^(9/4) * n^(9/16)).
G.f.: exp(Sum_{k>=1} sigma_7(k)*x^k/(k*(1 - x^(2*k)))). - Ilya Gutkovskiy, Oct 26 2018
MATHEMATICA
nmax = 30; CoefficientList[Series[Product[(1+x^k)^DivisorSigma[6, k], {k, 1, nmax}], {x, 0, nmax}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Mar 23 2018
STATUS
approved