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a(n) = C(2n,n)*Bell(n).
3

%I #11 May 25 2016 11:14:24

%S 1,2,12,100,1050,13104,187572,3009864,53281800,1028167140,21427077100,

%T 478684992240,11394223609132,287518731462200,7658231740945200,

%U 214521099763208400,6299407928974197330,193373975594104580880,6189939300884798312700,206159811915133359036600

%N a(n) = C(2n,n)*Bell(n).

%H Alois P. Heinz, <a href="/A124102/b124102.txt">Table of n, a(n) for n = 0..445</a>

%F a(n) = A056857(2n+1,n+1) = A056860(2n+1,n+1). - _Alois P. Heinz_, May 25 2016

%p with(combinat): a:=n->binomial(2*n,n)*bell(n): seq(a(n), n=0..20);

%t Table[Binomial[2n,n]*BellB[n],{n,0,20}] (* _Harvey P. Dale_, Apr 20 2012 *)

%Y Cf. A000110, A056857, A056860.

%K nonn

%O 0,2

%A _Zerinvary Lajos_, Nov 26 2006