Enumeration and Maximum Number of Maximal Irredundant Sets for Chordal Graphs

Abstract

In this paper we provide exponential-time algorithms to enumerate the maximal irredundant sets of chordal graphs and two of their subclasses. We show that the maximum number of maximal irredundant sets of a chordal graph is at most \(1.7549^n\), and these can be enumerated in time \(O(1.7549^n)\). For interval graphs, we achieve the better upper bound of \(1.6957^n\) for the number of maximal irredundant sets and we show that they can be enumerated in time \(O(1.6957^n)\). Finally, we show that forests have at most \(1.6181^n\) maximal irredundant sets that can be enumerated in time \(O(1.6181^n)\). We complement the latter result by providing a family of forests having at least \(1.5292^n\) maximal irredundant sets.