OFFSET
0,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..421
FORMULA
Convolution inverse of A288840.
a(n) ~ (-1)^n * 512 * Pi^12 * exp(Pi*sqrt(3)*n) * n / (3 * Gamma(1/3)^18). - Vaclav Kotesovec, Jun 03 2018
MATHEMATICA
terms = 12;
E6[x_] = 1 - 504*Sum[k^5*x^k/(1 - x^k), {k, 1, terms}];
E8[x_] = 1 + 480*Sum[k^7*x^k/(1 - x^k), {k, 1, terms}];
E6[x]/E8[x] + O[x]^terms // CoefficientList[#, x]& (* Jean-François Alcover, Feb 23 2018 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Feb 11 2018
STATUS
approved