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A201702 Number of unlabeled 5-trees on n nodes. 4
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
Allan Bickle, A Survey of Maximal k-degenerate Graphs and k-Trees, Theory and Applications of Graphs 0 1 (2024) Article 5.
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
Eric Weisstein's World of Mathematics, k-Tree
CROSSREFS
Column k=5 of A370770.
Cf. A054581 (unlabeled 2-trees), A078792 (unlabeled 3-trees), A078793 (unlabeled 4-trees).
Sequence in context: A143872 A130756 A078793 * A202037 A322754 A224917
KEYWORD
nonn
AUTHOR
Andrew R. Gainer, Dec 03 2011
STATUS
approved

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)