login
A094611
Number of unlabeled pentagonal 2-trees with n pentagons.
2
1, 1, 1, 3, 11, 56, 359, 2597, 20386, 167819, 1429815, 12500748, 111595289, 1013544057, 9340950309, 87176935700, 822559721606, 7836316493485, 75293711520236, 728968295958626, 7105984356424859, 69697524828651997, 687448151462822966, 6815174949649428254
OFFSET
0,4
LINKS
G. Labelle, C. Lamathe and P. Leroux, Labeled and unlabeled enumeration of k-gonal 2-trees
CROSSREFS
Column k=5 of A340811.
Cf. A054581.
Sequence in context: A036760 A000985 A207433 * A052442 A217034 A330351
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Jun 06 2004
EXTENSIONS
Terms a(21) and beyond from Andrew Howroyd, May 09 2021
STATUS
approved