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A counterexample to the rank-coloring conjecture

✍ Scribed by N. Alon; P. D. Seymour

Publisher: John Wiley and Sons
Year: 1989
Tongue: English
Weight: 140 KB
Volume: 13
Category: Article
ISSN: 0364-9024
DOI: 10.1002/jgt.3190130413

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✦ Synopsis

It has been conjectured by C. van Nuffelen that the chromatic number of any graph with at least one edge does not exceed the rank of its adjacency matrix. We give a counterexample, with chromatic number 32 and with an adjacency matrix of rank 29.

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