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arXiv · 1111.3277

Families of Small Regular Graphs of Girth 5

M. Abreu·G. Araujo-Pardo·C. Balbuena·D. Labbate
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Abstract

In this paper we obtain $(q+3)$--regular graphs of girth 5 with fewer vertices than previously known ones for $q=13,17,19$ and for any prime $q \ge 23$ performing operations of reductions and amalgams on the Levi graph $B_q$ of an elliptic semiplane of type ${\cal C}$. We also obtain a 13-regular graph of girth 5 on 236 vertices from $B_{11}$ using the same technique.

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M. Abreu, G. Araujo-Pardo, C. Balbuena, D. Labbate. 2011-11-14. Families of Small Regular Graphs of Girth 5. https://doi.org/10.1016/j.disc.2012.05.020

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