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A034753
Dirichlet convolution of 3^(n-1) with sigma(n).
0
1, 6, 13, 43, 87, 294, 737, 2304, 6610, 19962, 59061, 178111, 531455, 1596558, 4783371, 14355733, 43046739, 129161004, 387420509, 1162321341, 3486787421, 10460530422, 31381059633, 94143721320, 282429536998, 847290203850
OFFSET
1,2
FORMULA
a(n) ~ 3^(n-1). - Vaclav Kotesovec, Sep 11 2019
a(n) = Sum_{d|n} sigma(n/d)*3^(d-1). - Wesley Ivan Hurt, Dec 31 2023
MATHEMATICA
Table[Sum[DivisorSigma[1, n/d]*3^(d - 1), {d, Divisors[n]}], {n, 1, 25}] (* Vaclav Kotesovec, Sep 10 2019 *)
CROSSREFS
Cf. A000203.
Sequence in context: A216508 A057451 A239794 * A100905 A353964 A041489
KEYWORD
nonn
STATUS
approved