A243559 Number of simple connected graphs with n nodes that have no subgraph isomorphic to bull graph or K_4.

1, 1, 2, 5, 9, 26, 80, 340, 1690, 11432, 101142, 1228608, 20329150

Offset

1,3

Comments

K_4 is the complete graph with four vertices.

Links

Table of n, a(n) for n=1..13.

Travis Hoppe and Anna Petrone, Encyclopedia of Finite Graphs

T. Hoppe and A. Petrone, Integer sequence discovery from small graphs, arXiv preprint arXiv:1408.3644, 2014

F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version 29e68fa.

Crossrefs

Cf. A244427 (no bull subgraphs), A079574 (K_4 free graphs).

Sequence in context: A006405 A305189 A344394 * A334077 A136108 A026297

Adjacent sequences: A243556 A243557 A243558 * A243560 A243561 A243562

Keyword

nonn,more

Author

Travis Hoppe and Anna Petrone, Jun 06 2014

Extensions

a(11)-a(13) added using tinygraph by Falk Hüffner, Sep 23 2020

Status

approved