Title
Finding clubs in graph classes.
Abstract
For a positive integer s, an s-club in a graph G is a set of vertices that induces a subgraph of G of diameter at most s. We study a relation of clubs and cliques. For a positive integer s, we say that a graph class G has the s-clique-power property if for every graph G∈G, every maximal clique in Gs is an s-club in G. Our main combinatorial results show that both 4-chordal graphs and AT-free graphs have the s-clique-power property for all s≥2. This has various algorithmic consequences. In particular we show that a maximum s-club in G can be computed in polynomial time when G is a chordal bipartite or a strongly chordal or a distance hereditary graph. On weakly chordal graphs, we obtain a polynomial-time algorithm when s is an odd integer, which is best possible as the problem is NP-hard for even values of s. We complement these results by proving the NP-hardness of the problem for every fixed s on 4-chordal graphs. Finally, if G is an AT-free graph, we prove that the problem can be solved in polynomial time when s≥2, which gives an interesting contrast to the fact that the problem is NP-hard for s=1 on this graph class.
Year
DOI
Venue
2014
10.1016/j.dam.2014.04.016
Discrete Applied Mathematics
Keywords
Field
DocType
Clique,s-club,k-chordal graphs,AT-free graphs
Block graph,Discrete mathematics,Combinatorics,Forbidden graph characterization,Graph power,Interval graph,Chordal graph,Distance-hereditary graph,Pathwidth,Mathematics,Split graph
Journal
Volume
ISSN
Citations 
174
0166-218X
3
PageRank 
References 
Authors
0.41
15
4
Name
Order
Citations
PageRank
Petr A. Golovach176683.25
Pinar Heggernes284572.39
Dieter Kratsch31957146.89
Arash Rafiey433928.08