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A244537 Number of ordered unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 8.

%I A244537 #7 Jul 02 2014 11:43:39
%S A244537 1,0,0,0,0,0,0,0,8,17,18,19,20,21,22,23,116,325,676,1080,1540,2059,
%T A244537 2640,3286,5240,10241,20604,39305,68286,109705,165946,239629,351898,
%U A244537 552311,931070,1633871,2879668,4951860,8208631,13094200,20436400,31939817,50935060
%N A244537 Number of ordered unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 8.
%H A244537 Alois P. Heinz, <a href="/A244537/b244537.txt">Table of n, a(n) for n = 9..1000</a>
%p A244537 b:= proc(n, t, k) option remember; `if`(n=0,
%p A244537       `if`(t in [0, k], 1, 0), `if`(t>n, 0, add(b(j-1, k$2)*
%p A244537        b(n-j, max(0, t-1), k), j=1..n)))
%p A244537     end:
%p A244537 a:= n-> b(n-1, 8$2) -b(n-1, 9$2):
%p A244537 seq(a(n), n=9..55);
%Y A244537 Column k=8 of A244530.
%Y A244537 Cf. A244462.
%K A244537 nonn
%O A244537 9,9
%A A244537 _Joerg Arndt_ and _Alois P. Heinz_, Jun 29 2014