An infinite family of biprimitive semisymmetric graphs

A regular and edge transitive graph which is not vertex transitive is said to be semisymmetric Every semisymmetric graph is necessarily bipartite with the two parts having equal size and the automorphism group acting transitively on each of these two parts A semisymmet ric graph is called biprimitive if its automorphism group acts prim itively on each part In this paper a classi cation of biprimitive semisymmetric graphs arising from the action of the group PSL p p mod a prime acting on cosets of S is given resulting in several new in nite families of biprimitive semisymmetric graphs