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A245752 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 7.

%I A245752 #5 Aug 01 2014 12:36:23
%S A245752 3,23,114,474,1780,6179,20363,64441,197653,591131,1732165,4989933,
%T A245752 14171244,39760411,110402589,303808762,829504935,2249326273,
%U A245752 6062516975,16252409052,43361162336,115191492778,304834916107,803891596292,2113302899765,5539657831304
%N A245752 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 7.
%H A245752 Alois P. Heinz, <a href="/A245752/b245752.txt">Table of n, a(n) for n = 25..800</a>
%p A245752 b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
%p A245752       `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
%p A245752        b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
%p A245752     end:
%p A245752 a:= n-> b(n-1$2, 7$2) -b(n-1$2, 6$2):
%p A245752 seq(a(n), n=25..60);
%Y A245752 Column k=7 of A244523.
%K A245752 nonn
%O A245752 25,1
%A A245752 _Joerg Arndt_ and _Alois P. Heinz_, Jul 31 2014