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%I #5 Sep 04 2018 17:41:42
%S 0,1,1,2,4,9,20,48,115,285,717,1837,4753,12451,32878,87549,234654,
%T 632813,1715444,4672539,12780498,35091807,96684475,267223388,
%U 740690724,2058468456,5734614714,16011714554,44799497491,125587597952,352696620393,992168348175
%N Number of rooted trees with n nodes such that no more than seven isomorphic subtrees extend from the same node.
%H Alois P. Heinz, <a href="/A318854/b318854.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(7, 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=7 of A318757.
%K nonn
%O 0,4
%A _Alois P. Heinz_, Sep 04 2018
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