图X称为半传递图,如果X的自同构群Aut(X)传递地作用在顶点集和边集上,但不传递地作用在它的弧集上.该文主要研究了半传递图,证明了当3q︱p-1时,pq阶6度半传递图在同构意义下一定是某个Cayley图,从而给出了这类图的完全分拎.
A graph is half-arc-transitive if its automorphism group acts transitively on its vertex set and edge set,but not arc set.In this paper,it is proved that each hexavalent half-arc-transitive graph of order pq is a Cayley graph and such a graph exists if and only if p-1 is divisible by 3q,which is unique for a given order.Hence,we give a complete classification of hexavalent half-arc-transitive graph with pq vertices.