Automorphisms of graphs with intersection arrays {60, 45, 8; 1, 12, 50} and {49, 36, 8; 1, 6, 42}

Resumo

Automorphisms of distance-regular graphs are considered. It is proved that any graph with the intersection array {60, 45, 8; 1, 12, 50} is not vertex symmetric, and any graph with the intersection array {49, 36, 8; 1, 6, 42} is not edge symmetric.