A318852 Number of rooted trees with n nodes such that no more than five isomorphic subtrees extend from the same node.

0, 1, 1, 2, 4, 9, 20, 47, 113, 281, 706, 1807, 4671, 12223, 32245, 85777, 229670, 618732, 1675523, 4559000, 12456756, 34166545, 94034740, 259621512, 718846854, 1995610386, 5553500697, 15489256677, 43290763753, 121226491459, 340079258393, 955634312429

Offset

0,4

Links

Alois P. Heinz, Table of n, a(n) for n = 0..2138

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(5, 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=5 of A318757.

Sequence in context: A091500 A370718 A318799 * A052329 A199883 A036624

Adjacent sequences: A318849 A318850 A318851 * A318853 A318854 A318855

Keyword

nonn

Author

Alois P. Heinz, Sep 04 2018

Status

approved