This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A318854 #5 Sep 04 2018 17:41:42 %S A318854 0,1,1,2,4,9,20,48,115,285,717,1837,4753,12451,32878,87549,234654, %T A318854 632813,1715444,4672539,12780498,35091807,96684475,267223388, %U A318854 740690724,2058468456,5734614714,16011714554,44799497491,125587597952,352696620393,992168348175 %N A318854 Number of rooted trees with n nodes such that no more than seven isomorphic subtrees extend from the same node. %H A318854 Alois P. Heinz, <a href="/A318854/b318854.txt">Table of n, a(n) for n = 0..2136</a> %p A318854 h:= proc(n, m, t) option remember; `if`(m=0, binomial(n+t, t), %p A318854 `if`(n=0, 0, add(h(n-1, m-j, t+1), j=1..min(7, m)))) %p A318854 end: %p A318854 b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, %p A318854 add(b(n-i*j, i-1)*h(a(i), j, 0), j=0..n/i))) %p A318854 end: %p A318854 a:= n-> `if`(n<2, n, b(n-1$2)): %p A318854 seq(a(n), n=0..35); %Y A318854 Column k=7 of A318757. %K A318854 nonn %O A318854 0,4 %A A318854 _Alois P. Heinz_, Sep 04 2018