OFFSET
0,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..422
FORMULA
Convolution inverse of A288877.
a(n) ~ (-1)^n * 1024 * Pi^11 * exp(Pi*sqrt(3)*n) / (3^(3/2) * Gamma(1/3)^18). - Vaclav Kotesovec, Jun 03 2018
MATHEMATICA
terms = 13;
E2[x_] = 1 - 24*Sum[k*x^k/(1 - x^k), {k, 1, terms}];
E4[x_] = 1 + 240*Sum[k^3*x^k/(1 - x^k), {k, 1, terms}];
E2[x]/E4[x] + O[x]^terms // CoefficientList[#, x]& (* Jean-François Alcover, Feb 23 2018 *)
CROSSREFS
KEYWORD
sign
AUTHOR
Seiichi Manyama, Feb 11 2018
STATUS
approved