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arXiv · 2403.20049

Nonexistence of certain edge-girth-regular graphs

Leen Droogendijk
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Abstract

Edge-girth-regular graphs (abbreviated as \emph{egr} graphs) are regular graphs in which every edge is contained in the same number of shortest cycles. We prove that there is no $3$-regular \emph{egr} graph with girth $7$ such that every edge is on exactly $6$ shortest cycles, and there is no $3$-regular \emph{egr} graph with girth $8$ such that every edge is on exactly $14$ shortest cycles. This was conjectured by Goedgebeur and Jooken. A few other unresolved cases are settled as well.

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Leen Droogendijk. 2024-03-29. Nonexistence of certain edge-girth-regular graphs. https://arxiv.org/abs/2403.20049

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