Title
A Local Strengthening of Reed's Omega, Delta, Chi Conjecture for Quasi-line Graphs.
Abstract
Reed's omega, Delta, chi conjecture proposes that every graph satisfies chi <= inverted right perpendicular1/2 (Delta + 1 + omega)inverted left perpendicular; it is known to hold for all claw-free graphs. In this paper we consider a local strengthening of this conjecture. We prove the local strengthening for line graphs, then note that previous results immediately tell us that the local strengthening holds for all quasi-line graphs. Our proofs lead to polytime algorithms for constructing colorings that achieve our bounds: O(n(2)) for line graphs and O(n(3)m(2)) for quasi-line graphs. For line graphs, this is faster than the best known algorithm for constructing a coloring that achieves the bound of Reed's original conjecture.
Year
DOI
Venue
2013
10.1137/110847585
SIAM JOURNAL ON DISCRETE MATHEMATICS
Keywords
Field
DocType
graph coloring,chromatic number,line graph,quasi-line graph,Reed's conjecture
Discrete mathematics,Indifference graph,Combinatorics,Line graph,Chordal graph,Mathematical proof,Pathwidth,Conjecture,1-planar graph,Mathematics,Graph coloring
Journal
Volume
Issue
ISSN
27
1
0895-4801
Citations 
PageRank 
References 
5
0.57
7
Authors
4
Name
Order
Citations
PageRank
Maria Chudnovsky139046.13
Andrew D. King219218.88
Matthieu Plumettaz3974.96
Paul D. Seymour42786314.49