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%I #9 May 21 2018 03:14:26
%S 1,2,4,11,33,147,896,8683,131333,3065118
%N Number of perfectly contractile perfect graphs on n nodes.
%H S. Hougardy, <a href="http://www.or.uni-bonn.de/~hougardy/">Home Page</a>
%H S. Hougardy, <a href="http://dx.doi.org/10.1016/j.disc.2006.05.021">Classes of perfect graphs</a>, Discr. Math. 306 (2006), 2529-2571.
%H Jessica Shi, <a href="https://pdfs.semanticscholar.org/c264/67cd4a5f0adee094d7c19fd8a08a78b46793.pdf">Enumeration of unlabeled graph classes: A study of tree decompositions and related approaches</a>, 2015.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_, Oct 18 2006