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A201702 Number of unlabeled 5-trees on n nodes 3
0, 0, 0, 0, 1, 1, 1, 2, 5, 15, 64, 342, 2321, 18578, 168287, 1656209, 17288336, 188006362, 2105867058, 24108331027, 280638347609, 3310098377912, 39462525169310, 474697793413215, 5754095507495584, 70216415130786725, 861924378411516159, 10636562125193377459 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,8

COMMENTS

A k-tree is recursively defined as follows: K_k is a k-tree and any k-tree on n+1 vertices is obtained by joining a vertex to a k-clique in a k-tree on n vertices.

REFERENCES

Miklos Bona, editor, Handbook of Enumerative Combinatorics, CRC Press, 2015, page 328.

LINKS

Table of n, a(n) for n=1..28.

Andrew Gainer-Dewar, Gamma-Species and the Enumeration of k-Trees, Electronic Journal of Combinatorics, Volume 19 (2012), #P45. - From N. J. A. Sloane, Dec 15 2012

CROSSREFS

Cf. A054581 (unlabeled 2-trees), A078792 (unlabeled 3-trees), A078793 (unlabeled 4-trees).

Sequence in context: A143872 A130756 A078793 * A202037 A322754 A224917

Adjacent sequences:  A201699 A201700 A201701 * A201703 A201704 A201705

KEYWORD

nonn

AUTHOR

Andrew R. Gainer, Dec 03 2011

STATUS

approved

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Last modified October 15 05:43 EDT 2019. Contains 328026 sequences. (Running on oeis4.)