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%I #17 Mar 06 2023 08:02:45
%S 0,1,1,1,1,3,3,5,11,15,27,54,94,181,369,731,1502,3187
%N Number of unlabeled connected claw-free cubic graphs on 2n vertices.
%C A cubic graph is claw-free (contains no induced K_{1,3}) if and only if every vertex lies in a triangle. All graphs counted are simple (no loops or multiple edges).
%D A. Itzhakov and M. Codish, Breaking Symmetries with High Dimensional Graph Invariants and their Combination, Proceedings of the 20th International Conference on the Integration of Constraint Programming, Artificial Intelligence, and Operations Research (2023).
%H Gordon Royle, <a href="http://www.csse.uwa.edu.au/~gordon/data.html">Combinatorial Data</a>.
%e K_4 is claw-free and so a(2) = 1, while the triangular prism is the only claw-free cubic graph on 6 vertices, so a(3) = 1.
%Y Cf. A084657, A084658, A057848.
%K nonn,more
%O 1,6
%A _Gordon F. Royle_, Jun 02 2003
%E a(16)-a(18) from _Michael Codish_, Mar 05 2023
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