On colour-preserving automorphisms of Cayley graphs
نویسندگان
چکیده
We study the automorphisms of a Cayley graph that preserve its natural edge-colouring. More precisely, we are interested in groups G, such that every such automorphism of every connected Cayley graph on G has a very simple form: the composition of a left-translation and a group automorphism. We find classes of groups that have this property, and we determine the orders of all groups that do not have this property. We also have analogous results for automorphisms that permute the colours, rather than preserving them.
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