Semi-groups acting on context-free graphs

  • Géraud Sénizergues
Session 4: Languages and Processes
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1099)


Let Γ be a context-free graph. We give sufficient conditions on a semi-group of bisimulations H to ensure that the quotient HΓ is context-free. Using these sufficient conditions we show that the quotient Aut(Γ)Γ of Γ by its full group of automorphisms is always context-free.


infinite graphs ends pushdown automata automorphisms bisimulations groups semi-groups 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1996

Authors and Affiliations

  • Géraud Sénizergues
    • 1
    • 2
  1. 1.LaBRI Université de Bordeaux ITalenceFrance
  2. 2.LaBRI and UFR Math-infoUniversité BordeauxlTalence Cedex

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