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A318863
Number of rooted trees with n nodes such that six equals the maximal number of isomorphic subtrees extending from the same node.
2
0, 1, 1, 3, 8, 22, 60, 168, 466, 1306, 3677, 10400, 29503, 83964, 239523, 684855, 1961933, 5630300, 16182535, 46576693, 134225427, 387254945, 1118433179, 3233228736, 9354963666, 27089288339, 78501221909, 227643444368, 660560681614, 1917918979943, 5571738217340
OFFSET
6,4
LINKS
MAPLE
h:= proc(n, m, t, k) option remember; `if`(m=0, binomial(n+t, t),
`if`(n=0, 0, add(h(n-1, m-j, t+1, k), j=1..min(k, m))))
end:
b:= proc(n, i, k) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(b(n-i*j, i-1, k)*h(A(i, k), j, 0, k), j=0..n/i)))
end:
A:= (n, k)-> `if`(n<2, n, b(n-1$2, k)):
a:= n-> (k-> A(n, k)-A(n, k-1))(6):
seq(a(n), n=6..36);
CROSSREFS
Column k=6 of A318758.
Sequence in context: A318823 A318864 A318822 * A318821 A014397 A048503
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 04 2018
STATUS
approved