An antipodal distance-regular graph of diameter four or five is a covering graph of a connected strongly regular graph. We give existence conditions for these graphs and show for some types of strongly regular graphs that no nontrivial covers exist.
Distance regular graphs of diameter 3 and strongly regular graphs
β Scribed by A.E Brouwer
- Publisher
- Elsevier Science
- Year
- 1984
- Tongue
- English
- Weight
- 124 KB
- Volume
- 49
- Category
- Article
- ISSN
- 0012-365X
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β¦ Synopsis
In [1] N.L. Biggs mentions two parameter sets for distance regular graphs that are antipodal covers of a complete graph, for which existence of a corresponding graph was unknown. Here we settle both cases by proving that one does not exist, while there are exactly two nonisomorphic solutions to the other. We note some relations with strongly regular graphs and generalized quadrangles.
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