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A245125
Number of n-node rooted identity trees with thinning limbs and root outdegree (branching factor) 6.
2
2, 6, 23, 60, 162, 397, 960, 2223, 5085, 11355, 25088, 54654, 118051, 252601, 536973, 1133925, 2382281, 4980512, 10370545, 21512821, 44483291, 91708748, 188580249, 386854596, 791909788, 1617922147, 3299701619, 6718766927, 13660421145, 27736326713, 56246087592
OFFSET
20,1
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, 6$2):
seq(a(n), n=20..55);
CROSSREFS
Column k=6 of A245120.
Sequence in context: A168270 A222761 A298817 * A290954 A220213 A217200
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jul 12 2014
STATUS
approved