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%I #9 Apr 12 2024 07:50:01
%S 0,0,0,1,1,4,6,26,74,356,1655,9750,62009,448498,3554505,31000909,
%T 294772655,3047952802,34135465140
%N Number of 2-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 For n=4, the only example is the 4-cycle. For n=5, the only example is K(2,3).
%Y Cf. A371867, A371868.
%K nonn,hard,more
%O 1,6
%A _Brendan McKay_, Apr 09 2024