

A220822


Number of rooted binary leafmultilabeled trees with n leaves on the label set [5].


2



0, 0, 0, 0, 105, 2625, 42075, 554820, 6578550, 73169250, 781319370, 8122058850, 82922497890, 836339477160, 8366154130425, 83235403604220, 825247074255735, 8165187992777430, 80704316324506860, 797435573602269015, 7881226621071221625, 77939438593071188565
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OFFSET

1,5


LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..200
V. P. Johnson, Enumeration Results on Leaf Labeled Trees, Ph. D. Dissertation, Univ. Southern Calif., 2012.


MAPLE

b:= proc(n, k) option remember; `if`(n<2, k*n, `if`(n::odd, 0,
(t> t*(1t)/2)(b(n/2, k)))+add(b(i, k)*b(ni, k), i=1..n/2))
end:
a:= n> (k> add((1)^i*binomial(k, i)*b(n, ki), i=0..k))(5):
seq(a(n), n=1..30); # Alois P. Heinz, Sep 07 2019


CROSSREFS

Column 5 of A319541.
Sequence in context: A024198 A027788 A112497 * A166821 A166803 A262075
Adjacent sequences: A220819 A220820 A220821 * A220823 A220824 A220825


KEYWORD

nonn


AUTHOR

N. J. A. Sloane, Dec 22 2012


EXTENSIONS

Terms a(11) and beyond from Andrew Howroyd, Sep 23 2018


STATUS

approved



