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%I #7 Jul 02 2014 11:45:11
%S 1,0,0,0,0,0,0,0,0,9,19,20,21,22,23,24,25,26,144,406,841,1335,1891,
%T 2512,3201,3961,4795,7491,14467,28861,54626,94160,150101,225337,
%U 323016,446556,629454,949486,1545877,2639756,4558225,7716325,12629776,19928727,30372551
%N Number of ordered unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 9.
%H Alois P. Heinz, <a href="/A244538/b244538.txt">Table of n, a(n) for n = 10..1000</a>
%p b:= proc(n, t, k) option remember; `if`(n=0,
%p `if`(t in [0, k], 1, 0), `if`(t>n, 0, add(b(j-1, k$2)*
%p b(n-j, max(0, t-1), k), j=1..n)))
%p end:
%p a:= n-> b(n-1, 9$2) -b(n-1, 10$2):
%p seq(a(n), n=10..60);
%Y Column k=9 of A244530.
%Y Cf. A244463.
%K nonn
%O 10,10
%A _Joerg Arndt_ and _Alois P. Heinz_, Jun 29 2014