A244464 - OEIS

A244464

Number of unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 10.

1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 7, 12, 16, 21, 25, 30, 34, 39, 43, 52, 65, 88, 121, 165, 219, 285, 360, 447, 544, 661, 805, 998, 1256, 1613, 2085, 2709, 3500, 4496, 5709, 7201, 9016, 11277, 14108, 17738, 22410, 28484, 36330

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OFFSET

11,12

LINKS

Alois P. Heinz, Table of n, a(n) for n = 11..900

MAPLE

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

1, 0), `if`(i<1 or t>n, 0, add(binomial(b((i-1)$2, k$2)+j-1, j)*

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

end:

a:= n-> b(n-1$2, 10$2) -b(n-1$2, 11$2):

seq(a(n), n=11..80);