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A034770 Dirichlet convolution of Bell numbers with themselves. 0
1, 2, 4, 11, 30, 108, 406, 1764, 8284, 42324, 231950, 1357264, 8427194, 55289280, 381798704, 2765918869, 20960284294, 165729748096, 1364153612318, 11665484452558, 103448316471556, 949739632545452, 9013431476894646 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..23.

MATHEMATICA

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

CROSSREFS

Sequence in context: A275310 A102814 A193059 * A276687 A298891 A002387

Adjacent sequences:  A034767 A034768 A034769 * A034771 A034772 A034773

KEYWORD

nonn

AUTHOR

Erich Friedman

STATUS

approved

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Last modified August 1 11:49 EDT 2021. Contains 346385 sequences. (Running on oeis4.)