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A245128
Number of n-node rooted identity trees with thinning limbs and root outdegree (branching factor) 9.
2
6, 32, 140, 490, 1582, 4679, 13207, 35579, 92848, 235364, 583368, 1417164, 3386221, 7972754, 18536344, 42613503, 97001737, 218855237, 489889224, 1088756521, 2404139499, 5277595013, 11523611147, 25038756870, 54160808489, 116670213947, 250366691420, 535375247787
OFFSET
37,1
LINKS
MAPLE
b:= proc(n, i, h, v) option remember; `if`(n=0, `if`(v=0, 1, 0),
`if`(i<1 or v<1 or n<v, 0, add(binomial(A(i, min(i-1, h)), j)
*b(n-i*j, i-1, h, v-j), j=0..min(n/i, v))))
end:
A:= proc(n, k) option remember;
`if`(n<2, n, add(b(n-1$2, j$2), j=1..min(k, n-1)))
end:
a:= n-> b(n-1$2, 9$2):
seq(a(n), n=37..70);
CROSSREFS
Column k=9 of A245120.
Sequence in context: A202807 A203324 A027217 * A121333 A243026 A242542
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 12 2014
STATUS
approved