|
Search: id:A078792
|
|
|
| A078792 |
|
Number of unlabeled 3-trees on n vertices. |
|
+0
1
|
|
| 0, 0, 1, 1, 1, 2, 5, 15, 58, 275, 1505, 9003, 56931, 372973
(list; graph; listen)
|
|
|
OFFSET
|
1,6
|
|
|
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 new vertex to a k-clique in a k-tree on n vertices.
|
|
CROSSREFS
|
Cf. A036362(labeled 3-trees), A054581 (unlabeled 2-trees).
Sequence in context: A119611 A005976 A048192 this_sequence A030934 A030922 A030916
Adjacent sequences: A078789 A078790 A078791 this_sequence A078793 A078794 A078795
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Gordon Royle (gordon(AT)maths.uwa.edu.au), Dec 05 2002
|
|
|
Search completed in 0.002 seconds
|
