Mathematical logic, algebra and number theory

On automorphisms of a distance-regular graph with intersection array $\{243,220,1;1,4,243\}$

V. V. Bitkina

Severo-Osetinskii State University, str. Vatutina, 46, 362000, Vladikavkaz, Russia

Abstract: It was proved that a distance regular graph in which neighborhoods of vertices are strongly regular with parameters $(243,22,1,2)$ has intersection array $\{243,220,1;1,22,243\}$ or $\{243,220,1;1,4,243\}$. In this paper we found the automorphisms of a distance regular graph with intersection array $\{243,220,1;1,4,243\}$. In particular, this graph is not vertex-symmetric.

UDC: 519.17+512.54

MSC: 05C25

Received October 20, 2016, published January 24, 2017

DOI: 10.17377/semi.2017.14.004