A034747 Dirichlet convolution of Fibonacci numbers with sigma(n).

1, 4, 6, 13, 11, 30, 21, 52, 55, 94, 101, 234, 247, 448, 666, 1117, 1615, 2794, 4201, 7043, 11046, 18026, 28681, 47094, 75086, 122148, 196620, 319137, 514259, 834330, 1346301, 2181556, 3525006, 5707750, 9227631, 14939239, 24157855, 39100792

Offset

1,2

Links

Table of n, a(n) for n=1..38.

Formula

G.f.: Sum_{k>=1} sigma(k) * x^k/(1 - x^k - x^(2*k)). - Ilya Gutkovskiy, Jul 23 2019

a(n) ~ ((1+sqrt(5))/2)^n / sqrt(5). - Vaclav Kotesovec, Sep 11 2019

Mathematica

Table[Sum[DivisorSigma[1, n/d]*Fibonacci[d], {d, Divisors[n]}], {n, 1, 40}] (* Vaclav Kotesovec, Sep 10 2019 *)

Crossrefs

Cf. A000045, A000203.

Sequence in context: A003973 A341636 A349129 * A168015 A225939 A191199

Adjacent sequences: A034744 A034745 A034746 * A034748 A034749 A034750

Keyword

nonn

Author

Erich Friedman

Status

approved