Languages Defined by Generalized Equality Sets

  • Vesa Halava
  • Tero Harju
  • Hendrik Jan Hoogeboom
  • Michel Latteux
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2751)


We consider the generalized equality sets which are of the form E G (a,g 1,g 2) = { w | g 1(w) = ag 2(w)}, determined by instances of the generalized Post Correspondence Problem, where the morphisms g 1 and g 2 are nonerasing and a is a letter. We are interested in the family consisting of the languages h(E G (J)), where h is a coding and J is a shifted equality set of the above form. We prove several closure properties for this family.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Vesa Halava
    • 1
  • Tero Harju
    • 1
  • Hendrik Jan Hoogeboom
    • 2
  • Michel Latteux
    • 3
  1. 1.Department of Mathematics and TUCS – Turku Centre for Computer ScienceUniversity of TurkuTurkuFinland
  2. 2.Dept. of Comp. ScienceLeiden UniversityLeidenThe Netherlands
  3. 3.Université des Sciences et Technologies de LilleVilleneuve d’AscqFrance

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