Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-26T05:18:39.020Z Has data issue: false hasContentIssue false

Finite normal edge-transitive Cayley graphs

Published online by Cambridge University Press:  17 April 2009

Cheryl E. Praeger
Affiliation:
Department of Mathematics and Statistics, University of Western Australia, Nedlands WA 6907, Australia
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

An approach to analysing the family of Cayley graphs for a finite group G is given which identifies normal edge-transitive Cayley graphs as a sub-family of central importance. These are the Cayley graphs for G for which a subgroup of automorphisms exists which both normalises G and acts transitively on edges. It is shown that, for a nontrivial group G, each normal edge-transitive Cayley graph for G has at least one homomorphic image which is a normal edge-transitive Cayley graph for a characteristically simple quotient group of G. Moreover, given a normal edge-transitive Cayley graph ΓH for a quotient group G/H, necessary and sufficient conditions are obtained for the existence of a normal edge-transitive Cayley graph Γ for G which has ΓH as a homomorphic image, and a method for obtaining all such graphs Γ is given.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1999

References

[1]Baik, Y.G., Feng, Y.Q., Sim, H.S. and Xu, M.Y., ‘On the normality of Cayley graphs of Abelian groups’, Algebra Colloq. 5 (1998), 297304.Google Scholar
[2]Biggs, N., Algebraic graph theory (Cambridge University Press, Cambridge, 1974).CrossRefGoogle Scholar
[3]Chao, C.Y., ‘On the classification of symmetric graphs with a prime number of vertices’, Trans. Amer. Math. Soc. 158 (1971), 247256.CrossRefGoogle Scholar
[4]Du, S.F., Wang, R.J. and Xu, M.Y., ‘On the normality of Cayley digraphs of order twice a prime’, Australas. J. Combin. 18 (1998), 227234.Google Scholar
[5]Gorenstein, D., Finite groups (Harper, Evanston and London, 1968).Google Scholar
[6]Houlis, P., Quotients of normal-edge-transitive Cayley graphs, M.Sc. Thesis (University of Western Australia, 1998).Google Scholar
[7]Li, C.H., ‘On isomorphisms of connected Cayley graphs, III’, Bull. Austral. Math. Soc. 58 (1998), 137145.CrossRefGoogle Scholar
[8]McKay, B.D. and Praeger, C.E., ‘Vertex-transitive graphs which are not Cayley graphs, I’, J. Austral. Math. Soc. Ser. A 56 (1994), 5363.CrossRefGoogle Scholar
[9]Praeger, C.E.. ‘An O'Nan-Scott Theorem for finite quasiprimitive permutation groups and an application to 2-arc transitive graphs’, J. London Math. Soc. (2) 47 (1993), 227239.CrossRefGoogle Scholar
[10]Praeger, C.E., ‘Finite quasiprimitive graphs’, in Surveys in Combinatorics, 1997, (Bailey, R.A., Editor), London Mathematical Society Lecture Notes in Mathematics 241 (Cambridge University Press, Cambridge, 1997), pp. 6585.CrossRefGoogle Scholar
[11]Sims, C.C., ‘Computational methods in the study of permutation groups’, in Computational problems in abstract algebra, (Leech, J., Editor) (Pergamon Press, New York, 1970), pp. 169184.Google Scholar
[12]Xu, M.Y., ‘Automorphism groups and isomorphisms of Cayley graphs’, Discrete Math. 182 (1998), 309319.CrossRefGoogle Scholar