Title
Connected Greedy Colourings.
Abstract
A connected vertex ordering of a graph G is an ordering v(1) < v(2) < ... < v(n) of V (G) such that v(i) has at least one neighbour in {v(1),..., v(i-1)}, for every i is an element of {2,..., n}. A connected greedy colouring is a colouring obtained by the greedy algorithm applied to a connected vertex ordering. In this paper we study the parameter Gamma(c)( G), which is the maximum k such that G admits a connected greedy k-colouring, and chi(c)( G), which is the minimum k such that a connected greedy k-colouring of G exists. We prove that computing Gamma(c)(G) is NP-hard for chordal graphs and complements of bipartite graphs. We also prove that if G is bipartite, Gamma(c)(G) = 2. Concerning chi(c)(G), we first show that there is a k-chromatic graph G(k) with chi(c)(G(k)) > chi (G(k)), for every k >= 3. We then prove that for every graph G, chi(c)(G) <= chi(G) + 1. Finally, we prove that deciding if chi(c)(G) = chi(G), given a graph G, is a NP-hard problem.
Year
DOI
Venue
2014
10.1007/978-3-642-54423-1_38
Lecture Notes in Computer Science
Keywords
Field
DocType
Vertex colouring,Greedy colouring,Connected greedy colouring
Discrete mathematics,Graph,Combinatorics,Vertex (geometry),Computer science
Conference
Volume
ISSN
Citations 
8392
0302-9743
0
PageRank 
References 
Authors
0.34
7
7
Name
Order
Citations
PageRank
Fabrício Benevides1497.53
Victor Campos280.95
Mitre Dourado39018.43
Simon Griffiths400.34
Robert Morris5111.86
Leonardo Sampaio6495.30
Ana Silva7259.56