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Search: id:A078793
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A078793 Number of unlabeled 4-trees on n vertices. +0
1
0, 0, 0, 1, 1, 1, 2, 5, 15, 64, 331, 2150, 15817, 127194, 1077639 (list; graph; listen)
OFFSET

1,7

COMMENT

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.

LINKS

P. Di Francesco, P. Zinn-Justin and J.-B. Zuber, Determinant formulae for some tiling problems...

CROSSREFS

Cf. A036506 (labeled 4-trees).

Adjacent sequences: A078790 A078791 A078792 this_sequence A078794 A078795 A078796

Sequence in context: A030837 A143872 A130756 this_sequence A031154 A090091 A090130

KEYWORD

nonn

AUTHOR

Gordon Royle (gordon(AT)cs.uwa.edu.au), Dec 05 2002

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Last modified October 5 16:50 EDT 2008. Contains 144613 sequences.


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