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A318798
Number of rooted trees with n nodes such that no more than four subtrees of the same size extend from the same node.
2
0, 1, 1, 2, 4, 9, 19, 46, 110, 273, 684, 1746, 4503, 11758, 30943, 82118, 219337, 589477, 1592427, 4322386, 11781435, 32235285, 88502260, 243747792, 673238061, 1864400173, 5175591107, 14399672901, 40146278964, 112143682477, 313822403439, 879673332422
OFFSET
0,4
LINKS
MAPLE
g:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, add(
binomial(g((i-1)$2)+j-1, j)*g(n-i*j, i-1), j=0..min(4, n/i))))
end:
a:= n-> g((n-1)$2):
seq(a(n), n=0..40);
CROSSREFS
Column k=4 of A318753.
Sequence in context: A036718 A372102 A134964 * A318851 A052328 A133228
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Sep 03 2018
STATUS
approved