A337179 Number of geodetic graphs with n unlabeled vertices.
1, 1, 2, 4, 10, 23, 66, 185, 586, 1880, 6360, 21975, 78230, 283087, 1043329, 3895505, 14726263, 56234210, 216719056, 841857211, 3293753840, 12969219563
Offset: 1
Examples
For n=4 there are a(4)=4 geodetic graphs: a triangle with another edge attached to one vertex, an edge path of length 3, a tripod of 3 edges joined at a common vertex, and a complete graph on 4 vertices.
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Links
- John Cu, AMSI Vacation Research Scholar project, 2021
- Brendan McKay and Adolfo Piperno, nauty and Traces. [nauty and Traces are programs for computing automorphism groups of graphs and digraphs.]
- K. R. Parthasarathy and N. Srinivasan, Some general constructions of geodetic blocks, Journal of Combinatorial Theory, Series B (33) Issue 2, October 1982, pp. 121-136.
- Florian Stober and Armin Weiß, Geodetic Graphs: Experiments and New Constructions, arXiv:2308.08970 [math.CO], 2023.
- Eric Weisstein's World of Mathematics, Geodetic Graph
- Wikipedia, Geodetic graph
Programs
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Sage
See A337178.
Extensions
a(12)-a(22) from Florian Stober and Armin Weiß added by Murray Elder, Nov 14 2023
Comments