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A244462 Number of unlabeled rooted trees with n nodes such that the minimal outdegree of inner nodes equals 8. 3

%I #5 Jul 01 2014 19:31:10

%S 1,0,0,0,0,0,0,0,1,2,2,2,2,2,2,2,4,7,12,16,21,25,30,34,43,56,79,112,

%T 156,210,276,351,447,570,741,978,1314,1764,2367,3137,4131,5398,7058,

%U 9236,12161,16077,21340,28326,37573,49696,65623,86526,114122,150624

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

%H Alois P. Heinz, <a href="/A244462/b244462.txt">Table of n, a(n) for n = 9..900</a>

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

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

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

%p end:

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

%p seq(a(n), n=9..70);

%Y Column k=8 of A244454.

%Y Cf. A244537.

%K nonn

%O 9,10

%A _Joerg Arndt_ and _Alois P. Heinz_, Jun 29 2014

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Last modified March 2 08:26 EST 2024. Contains 370461 sequences. (Running on oeis4.)