Isomorphism for Graphs of Bounded Feedback Vertex Set Number

  • Stefan Kratsch
  • Pascal Schweitzer
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6139)


This paper presents an \({\mathcal O}(n^2)\) algorithm for deciding isomorphism of graphs that have bounded feedback vertex set number. This number is defined as the minimum number of vertex deletions required to obtain a forest. Our result implies that Graph Isomorphism is fixed-parameter tractable with respect to the feedback vertex set number. Central to the algorithm is a new technique consisting of an application of reduction rules that produce an isomorphism-invariant outcome, interleaved with the creation of increasingly large partial isomorphisms.


Chromatic Number Chordal Graph Reduction Rule Isomorphism Problem Graph Isomorphism 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Stefan Kratsch
    • 1
  • Pascal Schweitzer
    • 1
  1. 1.Max-Planck-Institut für InformatikSaarbrückenGermany

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