On the Koolen-Park inequality and Terwilliger graphs
نویسنده
چکیده
J.H. Koolen and J. Park proved a lower bound for the intersection number c2 of a distance-regular graph Γ. Moreover, they showed that a graph Γ, for which equality is attained in this bound, is a Terwilliger graph. We prove that Γ is the icosahedron, the Doro graph or the Conway–Smith graph if equality is attained and c2 > 2.
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عنوان ژورنال:
- Electr. J. Comb.
دوره 17 شماره
صفحات -
تاریخ انتشار 2010