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A034717 Dirichlet convolution of Catalan numbers (1,2,5,14...) with themselves. 0
1, 4, 10, 32, 84, 284, 858, 2916, 9749, 33760, 117572, 416692, 1485800, 5350596, 19390110, 70721256, 259289580, 955298168, 3534526380, 13128309200, 48932538330, 182965362424, 686119227300, 2579809144692, 9723892804668 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..25.

FORMULA

a(n) ~ 2^(2*n+1) / (sqrt(Pi) * n^(3/2)). - Vaclav Kotesovec, Sep 11 2019

MATHEMATICA

Table[Sum[CatalanNumber[n/d]*CatalanNumber[d], {d, Divisors[n]}], {n, 1, 30}] (* Vaclav Kotesovec, Sep 10 2019 *)

CROSSREFS

Sequence in context: A213106 A015796 A318562 * A295404 A001673 A017936

Adjacent sequences:  A034714 A034715 A034716 * A034718 A034719 A034720

KEYWORD

nonn

AUTHOR

Erich Friedman

STATUS

approved

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Last modified May 18 09:26 EDT 2021. Contains 343995 sequences. (Running on oeis4.)