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arXiv · 2311.09001

Non-geometric distance-regular graphs of diameter at least $3$ with smallest eigenvalue at least $-3$

Jack Koolen·Kefan Yu·Xiaoye Liang·Harrison Choi·Greg Markowsky
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Abstract

In this paper, we classify non-geometric distance-regular graphs of diameter at least $3$ with smallest eigenvalue at least $-3$. This is progress towards what is hoped to be an eventual complete classification of distance-regular graphs with smallest eigenvalue at least $-3$, analogous to existing classification results available in the case that the smallest eigenvalue is at least $-2$.

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Jack Koolen, Kefan Yu, Xiaoye Liang, Harrison Choi, Greg Markowsky. 2024-12-19. Non-geometric distance-regular graphs of diameter at least $3$ with smallest eigenvalue at least $-3$. https://arxiv.org/abs/2311.09001

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