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A366223
Number of unlabeled biconnected graphs on n vertices without 4-cycles or 5-cycles.
1
1, 0, 0, 1, 2, 6, 14, 44, 163, 722, 3683, 21555, 141664, 1035272, 8334650, 73511721, 707535039
OFFSET
3,5
EXAMPLE
For n=3, the only example is a triangle. For n=6, the only example is a hexagon. For n=7, in addition to the 7-cycle, there is a hexagon sharing an edge with a triangle.
CROSSREFS
Cf. A366220 (without biconnectivity condition).
Sequence in context: A151399 A299042 A152806 * A122109 A133155 A297708
KEYWORD
nonn,hard,more
AUTHOR
Brendan McKay, Oct 04 2023
STATUS
approved