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Formal languages consisting of primitive words

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

Abstract

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).

Keywords

Formal Language Cyclic Permutation Regular Language Great Common Divisor Finite Union 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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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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