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INVERT transform of A089835.
2

%I #14 Mar 03 2016 11:50:35

%S 2,28,704,26800,1404416,94890112,7887853568,779773444864,

%T 89407927009280,11666949886007296,1707352344419336192,

%U 276938622991133237248,49316570352062326636544,9565558797749164794511360,2007400581177856844629016576,453192947995950052758954115072

%N INVERT transform of A089835.

%H Alois P. Heinz, <a href="/A089836/b089836.txt">Table of n, a(n) for n = 1..150</a>

%F a(n) ~ 16^n * n! / (Pi*n^2). - _Vaclav Kotesovec_, Sep 05 2014

%p INVERT(A089835); INVERT([seq(A000108(n)*A000108(n)*(n+1)!,n=1..9)]);

%p a:= proc(n) option remember; local i; `if`(n<1, 1, add(a(n-i) *(2*i)!^2 /i!^3 /(i+1), i=1..n)) end: seq(a(n), n=1..20); # _Alois P. Heinz_, Apr 01 2009

%t a[n_] := a[n] = If[n < 1, 1, Sum[a[n - i] *(2 i)!^2 /i!^3 /(i + 1), {i, 1, n}]]; Array[a, 20] (* _Jean-François Alcover_, Mar 03 2016, adapted from Maple *)

%K nonn

%O 1,1

%A _Antti Karttunen_, Dec 05 2003

%E More terms from _Alois P. Heinz_, Apr 01 2009