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A034747 Dirichlet convolution of Fibonacci numbers with sigma(n). 0
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 (list; graph; refs; listen; history; text; internal format)
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: A130435 A028444 A003973 * A168015 A225939 A191199

Adjacent sequences:  A034744 A034745 A034746 * A034748 A034749 A034750

KEYWORD

nonn

AUTHOR

Erich Friedman

STATUS

approved

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Last modified July 4 14:51 EDT 2020. Contains 335448 sequences. (Running on oeis4.)