OFFSET
1,6
FORMULA
G.f. A(x) satisfies: A(x) = x + Sum_{k>=3} A(x^Fibonacci(k)).
MATHEMATICA
terms = 90; A[_] = 0; Do[A[x_] = x + Sum[A[x^Fibonacci[k]], {k, 3, 25}] + O[x]^(terms + 1) // Normal, terms + 1]; Rest[CoefficientList[A[x], x]]
f[n_] := f[n] = SeriesCoefficient[Sum[x^Fibonacci[k], {k, 3, 25}], {x, 0, n}]; a[n_] := If[n == 1, n, Sum[If[d < n, f[n/d] a[d], 0], {d, Divisors[n]}]]; Table[a[n], {n, 1, 90}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, May 10 2019
STATUS
approved