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4-chromatic projective graphs

✍ Scribed by Youngs, D. A.

Publisher: John Wiley and Sons
Year: 1996
Tongue: English
Weight: 464 KB
Volume: 21
Category: Article
ISSN: 0364-9024
DOI: 10.1002/(sici)1097-0118(199602)21:2<219::aid-jgt12>3.0.co;2-e

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✦ Synopsis

We construct a family of 4-chromatic graphs which embed on the projective plane, and characterize the edge-critical members. The family includes many well known graphs, and also a new sequence of graphs, which serve to improve Gallai's bound on the length of the shortest odd circuit in a 4-chromatic graph. 0

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