A267653 Number of unlabeled, connected graphs on n vertices which have no induced subgraph isomorphic to an R-graph.

1, 1, 2, 6, 21, 111, 818, 9825, 195759, 6622127, 368949015

Offset: 1

Author

Falk Hüffner, Jan 19 2016

Keywords

• nonn
• more

Comments

The R-graph has 6 vertices. 4 vertices form a cycle and both the other two vertices are adjacent to a single one of those 4.

Links

• F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version e8699da.

Crossrefs

Cf. A079570, the same for the cricket graph (like an R-graph, but with a triangle instead of a 4-cycle).