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Finding Optimal Routings in Hamming Graphs

✍ Scribed by Tian Khoon Lim; Cheryl E. Praeger


Publisher
Elsevier Science
Year
2002
Tongue
English
Weight
191 KB
Volume
23
Category
Article
ISSN
0195-6698

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✦ Synopsis


A routing R in a graph consists of a simple path p uv from u to v for each ordered pair of distinct vertices (u, v). We will call R optimal if all the paths p uv are shortest paths and if edges of the graph occur equally often in the paths of R. In 1994, SolΓ© gave a sufficient condition involving the automorphism group for a graph to have an optimal routing in this sense. Graphs which satisfy SolΓ©'s condition are called orbital regular graphs. It is often difficult to determine whether or not a given graph is orbital regular. In this paper, we give a necessary and sufficient condition for a Hamming graph to be orbital regular with respect to a certain natural subgroup of automorphisms.


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