A244537 - OEIS

A244537

Number of ordered unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 8.

1, 0, 0, 0, 0, 0, 0, 0, 8, 17, 18, 19, 20, 21, 22, 23, 116, 325, 676, 1080, 1540, 2059, 2640, 3286, 5240, 10241, 20604, 39305, 68286, 109705, 165946, 239629, 351898, 552311, 931070, 1633871, 2879668, 4951860, 8208631, 13094200, 20436400, 31939817, 50935060

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OFFSET

9,9

LINKS

Alois P. Heinz, Table of n, a(n) for n = 9..1000

MAPLE

b:= proc(n, t, k) option remember; `if`(n=0,

`if`(t in [0, k], 1, 0), `if`(t>n, 0, add(b(j-1, k$2)*

b(n-j, max(0, t-1), k), j=1..n)))

end:

a:= n-> b(n-1, 8$2) -b(n-1, 9$2):

seq(a(n), n=9..55);