## Abstract A graph having 27 vertices is described, whose automorphism group is transitive on vertices and undirected edges, but not on directed edges.
Graphs on which a dihedral group acts edge-transitively
β Scribed by Robin Sue Sanders
- Publisher
- Elsevier Science
- Year
- 1993
- Tongue
- English
- Weight
- 528 KB
- Volume
- 118
- Category
- Article
- ISSN
- 0012-365X
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β¦ Synopsis
In the present paper we find all the graphs on which a dihedral group acts edge-transitively.
First we explicitly build the permissible permutation representations of the dihedral group. Then we use this knowledge to find all the graphs on which a dihedral group acts edge-transitively.
These graphs fall into nine types, most of which are not vertex-transitive.
The graphs which are both vertex-transitive and edge-transitive belong to a previously studied family of graphs -the well-known circulant graphs. The nonvertex-transitive graphs fall into two broad classes ~ disjoint copies of complete bipartite graphs and 'pseudo-cycles' which are related to the tensor product of a complete bipartite graph and an even cycle.
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