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Graph properties and hypergraph colourings

โœ Scribed by Jason I. Brown; Derek G. Corneil


Publisher
Elsevier Science
Year
1991
Tongue
English
Weight
855 KB
Volume
98
Category
Article
ISSN
0012-365X

No coin nor oath required. For personal study only.

โœฆ Synopsis


Given a graph property P, graph G and integer k 20, a P k-colouring of G is a function Jr:V(G)+ (1,.

. ) k} such that the subgraph induced by each colour class has property P.

When P is closed under induced subgraphs, we can construct a hypergraph HG such that G is P k-colourable iff Hg is k-colourable. This correlation enables us to derive interesting new results in hypergraph chromatic theory from a 'graphic' approach.

In particular, we build vertex critical hypergraphs that are not edge critical, construct uniquely colourable hypergraphs with few edges and find graph-to-hypergraph transformations that preserve chromatic numbers.


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