OFFSET
1,28
FORMULA
G.f.: x * (1 + Sum_{n>=1} lambda(n)*a(n)*x^n/(1 - x^n)).
MATHEMATICA
a[n_] := a[n] = Sum[LiouvilleLambda[d] a[d], {d, Divisors[n - 1]}]; a[1] = 1; Table[a[n], {n, 1, 100}]
a[n_] := a[n] = SeriesCoefficient[x (1 + Sum[LiouvilleLambda[k] a[k] x^k/(1 - x^k), {k, 1, n - 1}]), {x, 0, n}]; Table[a[n], {n, 1, 100}]
CROSSREFS
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, May 01 2019
STATUS
approved