Formal languages consisting of primitive words

  • P. Dömösi
  • S. Horváth
  • M. Ito
  • L. Kászonyi
  • M. Katsura
Part of the Lecture Notes in Computer Science book series (LNCS, volume 710)


Let Q be the set of primitive words over a finite alphabet having at least two letters. We prove that Q has two rather strong context-free-like properties. The first one is that Q satisfies the nonempty, strong variant of Bader and Moura's iteration condition, and the second one is that intersecting Q with any member of a special, infinite family of regular languages, we get a context-free language. We also present two further related results. It remains an unsolved problem whether Q is non-context-free (we conjecture this).


Formal Language Cyclic Permutation Regular Language Great Common Divisor Finite Union 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • P. Dömösi
    • 1
  • S. Horváth
    • 2
  • M. Ito
    • 3
  • L. Kászonyi
    • 2
  • M. Katsura
    • 3
  1. 1.Dept. of Mathematics and InformaticsL. Kossuth UniversityDebrecenHungary
  2. 2.Dept. of Computer ScienceL. Eötvös UniversityBudapestHungary
  3. 3.Dept. of MathematicsKyoto Sangyo UniversityKyotoJapan

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