Computing Sharp 2-Factors in Claw-Free Graphs

  • Hajo Broersma
  • Daniël Paulusma
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5162)


In a recently submitted paper we obtained an upper bound for the minimum number of components of a 2-factor in a claw-free graph. This bound is sharp in the sense that there exist infinitely many claw-free graphs for which the bound is tight. In this paper we extend these results by presenting a polynomial algorithm that constructs a 2-factor of a claw-free graph with minimum degree at least four whose number of components meets this bound. As a byproduct we show that the problem of obtaining a minimum 2-factor (if it exists) is polynomially solvable for a subclass of claw-free graphs. As another byproduct we give a short constructive proof for a result of Ryjáček, Saito & Schelp.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Hajo Broersma
    • 1
  • Daniël Paulusma
    • 1
  1. 1.Department of Computer ScienceDurham UniversityDurhamUnited Kingdom

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