There does not exist a distance-regular graph with intersection array $\{80, 54,12; 1, 6, 60\}$
Combinatorics
2018-09-27 v1
Abstract
In this paper we will show that there does not exist a distance-regular graph with intersection array . We first show that a local graph of does not contain a coclique with 5 vertices, and then we prove that the graph is geometric by showing that consists of 4 disjoint cliques with 20 vertices. Then we apply a result of Koolen and Bang to the graph , and we could obtain that there is no such a distance-regular graph.
Cite
@article{arxiv.1809.10029,
title = {There does not exist a distance-regular graph with intersection array $\{80, 54,12; 1, 6, 60\}$},
author = {Jack H. Koolen and Quaid Iqbal and Jongyook Park and Masood Ur Rehman},
journal= {arXiv preprint arXiv:1809.10029},
year = {2018}
}
Comments
15 pages