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%I #5 Sep 04 2018 18:03:07
%S 0,1,1,2,4,9,20,48,115,286,719,1841,4764,12481,32960,87776,235286,
%T 634585,1720432,4686643,12820514,35205695,97009447,268152808,
%U 743354184,2066114828,5756601016,16075023964,44982030666,126114489722,354219135234,996572101259
%N Number of rooted trees with n nodes such that no more than nine isomorphic subtrees extend from the same node.
%H Alois P. Heinz, <a href="/A318856/b318856.txt">Table of n, a(n) for n = 0..2136</a>
%p h:= proc(n, m, t) option remember; `if`(m=0, binomial(n+t, t),
%p `if`(n=0, 0, add(h(n-1, m-j, t+1), j=1..min(9, m))))
%p end:
%p b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
%p add(b(n-i*j, i-1)*h(a(i), j, 0), j=0..n/i)))
%p end:
%p a:= n-> `if`(n<2, n, b(n-1$2)):
%p seq(a(n), n=0..35);
%Y Column k=9 of A318757.
%K nonn
%O 0,4
%A _Alois P. Heinz_, Sep 04 2018
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