On the isomorphism of graphs with few P4s

  • Luitpold Babel
  • Stephan Olariu
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1017)


We present new classes of graphs for which the isomorphism problem can be solved in polynomial time. These graphs are characterized by containing — in some local sense — only a small number of induced paths of length three. As it turns out, every such graph has a unique tree representation: the internal nodes correspond to three types of graph operations and the leaves are basic graphs with a simple structure. The paper extends and generalizes results on cographs, P4-reducible graphs, and P4-sparse graphs.


Polynomial Time Interval Graph Tree Representation Isomorphism Problem Arbitrary Graph 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • Luitpold Babel
    • 1
  • Stephan Olariu
    • 2
  1. 1.Institut für MathematikTechnische UniversitÄt MünchenMünchenGermany
  2. 2.Department of Computer ScienceOld Dominion UniversityNorfolkUSA

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