A245751 Number of identity trees with n nodes where the maximal outdegree (branching factor) equals 6.

3, 15, 70, 256, 884, 2840, 8788, 26238, 76511, 218462, 614003, 1702291, 4667792, 12678438, 34163511, 91424125, 243210889, 643652954, 1695711086, 4449529462, 11634279616, 30324707572, 78819222196, 204348623105, 528597552113, 1364545143938, 3515960193715

Offset

20,1

Links

Alois P. Heinz, Table of n, a(n) for n = 20..1000

Maple

b:= proc(n, i, t, k) option remember; `if`(n=0, 1,
      `if`(i<1, 0, add(binomial(b(i-1$2, k$2), j)*
       b(n-i*j, i-1, t-j, k), j=0..min(t, n/i))))
    end:
a:= n-> b(n-1$2, 6$2) -b(n-1$2, 5$2):
seq(a(n), n=20..60);

Crossrefs

Column k=6 of A244523.

Sequence in context: A318967 A277370 A213140 * A033876 A291031 A359405

Adjacent sequences: A245748 A245749 A245750 * A245752 A245753 A245754

Keyword

nonn

Author

Joerg Arndt and Alois P. Heinz, Jul 31 2014

Status

approved