OFFSET
0,11
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..10000
FORMULA
G.f.: exp(Sum_{k>=1} Sum_{j>=1} mu(j)^k*x^(j*k)/k).
MATHEMATICA
nmax = 65; CoefficientList[Series[Product[1/(1 - MoebiusMu[k] x^k), {k, 1, nmax}], {x, 0, nmax}], x]
nmax = 65; CoefficientList[Series[Exp[Sum[Sum[MoebiusMu[j]^k x^(j k)/k, {j, 1, nmax}], {k, 1, nmax}]], {x, 0, nmax}], x]
a[n_] := a[n] = If[n == 0, 1, Sum[Sum[d MoebiusMu[d]^(k/d), {d, Divisors[k]}] a[n - k], {k, 1, n}]/n]; Table[a[n], {n, 0, 65}]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Feb 07 2019
STATUS
approved