On the Automorphism Group of an Antipodal Tight Graph of Diameter 4 with Parameters (5, 7, r)

Аннотация

It is proved that the automorphism group of every AT4(5, 7, r)-graph acts intransitively on the set of its arcs. Moreover, it is established that the automorphism group of any strongly regular graph with parameters (329, 40, 3, 5) acts intransitively on the set of its vertices.