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arXiv · 1012.2632

There are only finitely many distance-regular graphs with valency k at least three, fixed ratio k2/k and large diameter

Jongyook Park·Jack H. Koolen·Greg Markowsky
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Abstract

In this paper, we show that for given positive integer C, there are only finitely many distance-regular graphs with valency k at least three, diameter D at least six and k2/k<=C. This extends a conjecture of Bannai and Ito.

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Jongyook Park, Jack H. Koolen, Greg Markowsky. 2010-12-13. There are only finitely many distance-regular graphs with valency k at least three, fixed ratio k2/k and large diameter. https://arxiv.org/abs/1012.2632

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