Abstract
J.H. Koolen and J. Park proved a lower bound for the intersection number $c_2$ of a distance-regular graph $\Gamma$. Moreover, they showed that a graph $\Gamma$, for which equality is attained in this bound, is a Terwilliger graph. We prove that $\Gamma$ is the icosahedron, the Doro graph or the Conway–Smith graph if equality is attained and $c_2\ge 2$.
Publisher
The Electronic Journal of Combinatorics
Subject
Computational Theory and Mathematics,Geometry and Topology,Theoretical Computer Science,Applied Mathematics,Discrete Mathematics and Combinatorics
Cited by
4 articles.
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