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A034755 Dirichlet convolution of 3^(n-1) with Catalan numbers. 0
1, 4, 11, 35, 95, 300, 861, 2658, 8009, 24668, 75845, 236401, 739453, 2338348, 7457697, 24047361, 78404391, 258796668, 865059189, 2929559709, 10050907467, 34926729660, 122863623249, 437203156566, 1572333684939, 5709236166372 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..26.

FORMULA

a(n) ~ 2^(2*n-2) / (sqrt(Pi) * n^(3/2)). - Vaclav Kotesovec, Sep 11 2019

MATHEMATICA

Table[Sum[CatalanNumber[n/d - 1]*3^(d - 1), {d, Divisors[n]}], {n, 1, 25}] (* Vaclav Kotesovec, Sep 10 2019 *)

CROSSREFS

Sequence in context: A149235 A149236 A135919 * A297608 A034756 A029853

Adjacent sequences:  A034752 A034753 A034754 * A034756 A034757 A034758

KEYWORD

nonn

AUTHOR

Erich Friedman

STATUS

approved

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Last modified June 20 09:25 EDT 2021. Contains 345162 sequences. (Running on oeis4.)