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%I #8 Apr 10 2024 09:34:21
%S 1,1,1,3,5,16,41,154,560,2550,12404,69536,428698,2947229,22288540,
%T 185226859,1682006569,16635022967,178525323313
%N Number of connected chordal bipartite graphs on n unlabeled vertices.
%C A chordal bipartite graph is a bipartite graph with no induced cycles longer than 4-cycles. Note that this is not the same as a bipartite graph which is chordal, as that would exclude all cycles.
%H Brendan McKay, <a href="https://users.cecs.anu.edu.au/~bdm/nauty/">nauty software </a> that can generate these graphs.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Chordal_bipartite_graph">Chordal bipartite graph</a>.
%e The 3 examples for n=4 are the 4-cycle, the star, and the path.
%Y Cf. A371867, A371869.
%K nonn,hard,more
%O 1,4
%A _Brendan McKay_, Apr 09 2024