A318797 Number of rooted trees with n nodes such that no more than three subtrees of the same size extend from the same node.

0, 1, 1, 2, 4, 8, 18, 43, 102, 250, 623, 1579, 4042, 10470, 27350, 72034, 190956, 509259, 1365271, 3677522, 9947145, 27007988, 73582758, 201103314, 551190098, 1514683667, 4172470962, 11519509386, 31869341642, 88337853393, 245301368188, 682307613945

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..2158

Maple

g:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, add(
      binomial(g((i-1)$2)+j-1, j)*g(n-i*j, i-1), j=0..min(3, n/i))))
    end:
a:= n-> g((n-1)$2):
seq(a(n), n=0..40);

Crossrefs

Column k=3 of A318753.

Sequence in context: A024428 A330269 A049075 * A318850 A052327 A059221

Adjacent sequences: A318794 A318795 A318796 * A318798 A318799 A318800

Keyword

nonn

Author

Alois P. Heinz, Sep 03 2018

Status

approved