

A079575


Number of unlabeled, connected graphs on n vertices with no induced subgraph isomorphic to a bullgraph.


2



1, 1, 2, 6, 20, 93, 480, 2960, 19475, 140851, 1116717, 10329833, 121557264
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OFFSET

1,3


COMMENTS

A bullgraph is formed by adding a 5th vertex to a 4path adjacent only to the middle two vertices on the path.


LINKS

Table of n, a(n) for n=1..13.
C. De Simone and A. Sassano, Stability number of bull and chairfree graphs, Discrete Appl. Math. 41 (1993) 121129.
Travis Hoppe and Anna Petrone, Encyclopedia of Finite Graphs
Falk Hüffner, tinygraph, software for generating integer sequences based on graph properties, version ece94ef.
Eric Weisstein's World of Mathematics, Bull Graph


CROSSREFS

Cf. A244427 (no bull subgraph).
Sequence in context: A009244 A104985 A210690 * A078564 A079576 A079570
Adjacent sequences: A079572 A079573 A079574 * A079576 A079577 A079578


KEYWORD

nonn,more


AUTHOR

Jim Nastos, Jan 24 2003


EXTENSIONS

a(10)a(13) added using tinygraph by Falk Hüffner, Jan 15 2016


STATUS

approved



