A318798 Number of rooted trees with n nodes such that no more than four subtrees of the same size extend from the same node.

0, 1, 1, 2, 4, 9, 19, 46, 110, 273, 684, 1746, 4503, 11758, 30943, 82118, 219337, 589477, 1592427, 4322386, 11781435, 32235285, 88502260, 243747792, 673238061, 1864400173, 5175591107, 14399672901, 40146278964, 112143682477, 313822403439, 879673332422

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..2143

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(4, n/i))))
    end:
a:= n-> g((n-1)$2):
seq(a(n), n=0..40);

Crossrefs

Column k=4 of A318753.

Sequence in context: A036718 A372102 A134964 * A318851 A052328 A133228

Adjacent sequences: A318795 A318796 A318797 * A318799 A318800 A318801

Keyword

nonn

Author

Alois P. Heinz, Sep 03 2018

Status

approved