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Chromatic numbers of hypergraphs and coverings of graphs

✍ Scribed by Zevi Miller; Heinrich Müller

Publisher: John Wiley and Sons
Year: 1981
Tongue: English
Weight: 284 KB
Volume: 5
Category: Article
ISSN: 0364-9024
DOI: 10.1002/jgt.3190050311

No coin nor oath required. For personal study only.

✦ Synopsis

Burr recently proved [3] that for positive integers m , , m 2 , . . , , m, and any graph G we have x(G) 5 &, if and only if G can be expressed as the edge disjoint union of subgraphs F, satisfying x(F,) 5 m,. This theorem is generalized to hypergraphs. By suitable interpretations the generalization is then used to deduce propositions on coverings of graphs. k , = I

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