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A371868
Number of connected chordal bipartite graphs on n unlabeled vertices.
2
1, 1, 1, 3, 5, 16, 41, 154, 560, 2550, 12404, 69536, 428698, 2947229, 22288540, 185226859, 1682006569, 16635022967, 178525323313
OFFSET
1,4
COMMENTS
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.
LINKS
Brendan McKay, nauty software that can generate these graphs.
EXAMPLE
The 3 examples for n=4 are the 4-cycle, the star, and the path.
CROSSREFS
Sequence in context: A300533 A221783 A368409 * A243321 A099101 A208819
KEYWORD
nonn,hard,more
AUTHOR
Brendan McKay, Apr 09 2024
STATUS
approved