OFFSET
1,1
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..700
FORMULA
a(n) = Sum_{d|n} d * A288968(d).
G.f.: 1/12 * E_4/E_2 - 1/12 * E_2.
a(n) ~ 1 / r^n, where r = A211342 = 0.037276810296451658150980785651644618... is the root of the equation Sum_{k>=1} A000203(k) * r^k = 1/24. - Vaclav Kotesovec, Jul 09 2017
EXAMPLE
MATHEMATICA
nmax = 20; Rest[CoefficientList[Series[24*x*Sum[k*DivisorSigma[1, k]*x^(k-1), {k, 1, nmax}]/(1 - 24*Sum[DivisorSigma[1, k]*x^k, {k, 1, nmax}]), {x, 0, nmax}], x]] (* Vaclav Kotesovec, Jul 09 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jul 09 2017
STATUS
approved