摘要

A Cayley graph Cay(G, S) on a group G with respect to a Cayley subset S is said to be normal if the right regular representation R(G) of G is normal in the full automorphism group of Cay(G, S). For a positive integer n, let Gamma(n), be a graph with vertex set {x(i), y(i) vertical bar Z(2n)} edge set {{x(i), x(i+1)}, {y(i), y(i+1)}, {x(2i), y(2i+1)}, {x(2i) , y(2i+1)} vertical bar i is an element of Z(2n)}. In this paper, it is shown that Gamma(r), is a Cayley graph and its full automorphism group is isomorphic to Z(2)(3) x S-3 for n = 2, and to Z(2)(n) x D-2n, for n > 2. Furthermore, we determine all pairs of G and S such that Gamma(n) = Cay(G, S) is non-normal for G. Using this, all connected cubic non-normal Cayley graphs of order 8p are constructed explicitly for each prime p.

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