Title
Join colourings of chordal graphs
Abstract
We consider certain partition problems typified by the following two questions. When is a given graph the join of two k -colourable graphs? When is a given graph the join of a k -colourable graph and a graph whose complement is k -colourable? We focus on the class of chordal graphs, and employ the language of matrix partitions. Our emphasis is on forbidden induced subgraph characterizations. We describe all chordal minimal obstructions to the existence of such partitions; they are surprisingly small and regular. We also give another characterization which yields a more efficient recognition algorithm. By contrast, most of these partition problems are NP-complete if chordality is not assumed.
Year
DOI
Venue
2015
10.1016/j.disc.2015.06.005
Discrete Mathematics
Keywords
Field
DocType
Graph partition,Graph homomorphism,Forbidden subgraph characterization,Chordal graph,Split graph
Discrete mathematics,Block graph,Outerplanar graph,Combinatorics,Interval graph,Forbidden graph characterization,Chordal graph,Distance-hereditary graph,Cograph,Mathematics,Split graph
Journal
Volume
Issue
ISSN
338
12
0012-365X
Citations 
PageRank 
References 
1
0.36
11
Authors
2
Name
Order
Citations
PageRank
Pavol Hell12638288.75
Pei-Lan Yen210.36