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A260813 Number of trivalent bipartite connected simple graphs with 2n nodes and girth at least 8. 1
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 3, 10, 101, 2510, 79605, 2607595, 81716416, 2472710752 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,19
COMMENTS
The null graph on 0 vertices is vacuously connected, 3-regular, and bipartite; since it is acyclic, it has infinite girth.
LINKS
G. Brinkmann, Fast generation of cubic graphs, Journal of Graph Theory, 23(2):139-149, 1996.
G. Brinkmann, J. Goedgebeur and B.D. McKay, The Minimality of the Georges-Kelmans Graph, arXiv:2101.00943 [math.CO], 2021.
House of Graphs, Cubic bipartite graphs
CROSSREFS
Connected 3-regular simple graphs with girth at least g: A185131 (triangle); chosen g: A002851 (g=3), A014371 (g=4), A014372 (g=5), A014374 (g=6), A014375 (g=7), A014376 (g=8).
Connected bipartite trivalent simple graphs with girth at least g: A006823 (g=4), A260811 (g=6), this sequence (g=8).
Sequence in context: A013268 A015487 A326428 * A062013 A023372 A025541
KEYWORD
nonn,more,hard
AUTHOR
Dylan Thurston, Jul 31 2015
EXTENSIONS
a(23)-a(24) from the House-of-Graphs added by R. J. Mathar, Sep 29 2017
a(25)-a(26) from Jan Goedgebeur, Aug 17 2021
STATUS
approved

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Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)