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A245751 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 6. 2

%I

%S 3,15,70,256,884,2840,8788,26238,76511,218462,614003,1702291,4667792,

%T 12678438,34163511,91424125,243210889,643652954,1695711086,4449529462,

%U 11634279616,30324707572,78819222196,204348623105,528597552113,1364545143938,3515960193715

%N Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 6.

%H Alois P. Heinz, <a href="/A245751/b245751.txt">Table of n, a(n) for n = 20..1000</a>

%p b:= proc(n, i, t, k) option remember; `if`(n=0, 1,

%p `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*

%p b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))

%p end:

%p a:= n-> b(n-1$2, 6$2) -b(n-1$2, 5$2):

%p seq(a(n), n=20..60);

%Y Column k=6 of A244523.

%K nonn

%O 20,1

%A _Joerg Arndt_ and _Alois P. Heinz_, Jul 31 2014

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Last modified July 12 05:35 EDT 2020. Contains 335658 sequences. (Running on oeis4.)