login
A318855
Number of rooted trees with n nodes such that no more than eight isomorphic subtrees extend from the same node.
2
0, 1, 1, 2, 4, 9, 20, 48, 115, 286, 718, 1840, 4761, 12473, 32938, 87716, 235119, 634120, 1719126, 4682961, 12810091, 35176098, 96925138, 267912073, 742665243, 2064139425, 5750927105, 16058701943, 44935012272, 125978876163, 353827545217, 995440198833
OFFSET
0,4
LINKS
MAPLE
h:= proc(n, m, t) option remember; `if`(m=0, binomial(n+t, t),
`if`(n=0, 0, add(h(n-1, m-j, t+1), j=1..min(8, m))))
end:
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(b(n-i*j, i-1)*h(a(i), j, 0), j=0..n/i)))
end:
a:= n-> `if`(n<2, n, b(n-1$2)):
seq(a(n), n=0..35);
CROSSREFS
Column k=8 of A318757.
Sequence in context: A145546 A292553 A318802 * A255639 A216062 A034826
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 04 2018
STATUS
approved