A345323 Number of unlabeled 2-connected simple bipartite graphs with no cycles of length 4.

1, 0, 2, 1, 6, 6, 28, 53, 229, 712, 3336, 15099, 82419, 477584, 3086563, 21566457, 164113460, 1350167015, 12007072739, 115165535180

Offset

6,3

Comments

Also: Number of unlabeled 2-connected simple bipartite graphs with girth at least 6.

Links

Table of n, a(n) for n=6..25.

Example

For n=8 the a(8)=2 solutions are an 8-cycle and a theta graph consisting of two vertices joined by three paths of length 3.

Crossrefs

Sequence in context: A113979 A053442 A019082 * A052636 A172430 A325139

Adjacent sequences: A345320 A345321 A345322 * A345324 A345325 A345326

Keyword

nonn,hard,more

Author

Brendan McKay, Jun 14 2021

Status

approved