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Merging in Antipodal Distance-Regular Graphs

✍ Scribed by A. Jurisic

Publisher: Elsevier Science
Year: 1994
Tongue: English
Weight: 320 KB
Volume: 62
Category: Article
ISSN: 0095-8956
DOI: 10.1006/jctb.1994.1066

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✦ Synopsis

Merging (also called fusion) is studied in antipodal distance-regular graphs. The conditions are determined under which merging the first and the last classes in an antipodal distance-regular graph produces a distance-regular graph. Conversely, given a distance-regular graph with the same intersection array as the merged graph and a certain clique partition, an antipodal distance-regular graph is constructed. This gives us a characterization of a class of antipodal distance-regular graphs with a class of regular near polygons containing a certain spread, which generalizes Brouwer's characterization of a class of distance-regular graphs of diameter 3 with generalized quadrangles containing a spread. 1994 Academic Press, Inc.

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