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A034774 Dirichlet convolution of d(n) (# of divisors) with Catalan numbers. 0
1, 3, 4, 10, 16, 52, 134, 446, 1437, 4896, 16798, 58896, 208014, 743170, 2674476, 9695727, 35357672, 129647751, 477638702, 1767272976, 6564120692, 24466300618, 91482563642, 343059732248, 1289904147355, 4861946817482 (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]*DivisorSigma[0, d], {d, Divisors[n]}], {n, 1, 25}] (* Vaclav Kotesovec, Sep 10 2019 *)

CROSSREFS

Sequence in context: A081160 A051437 A224073 * A342536 A172416 A317883

Adjacent sequences:  A034771 A034772 A034773 * A034775 A034776 A034777

KEYWORD

nonn

AUTHOR

Erich Friedman

STATUS

approved

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Last modified October 26 06:08 EDT 2021. Contains 348257 sequences. (Running on oeis4.)