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Fixed Point Approach to Commutation of Languages

  • Karel CulikII
  • Juhani Karhumäki
  • Petri Salmela
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2950)

Abstract

We show that the maximal set commuting with a given regular set – its centralizer – can be defined as the maximal fixed point of a certain language operator. Unfortunately, however, an infinite number of iterations might be needed even in the case of finite languages.

Keywords

Regular Language Point Approach Free Semigroup Language Operator Left Quotient 
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 2003

Authors and Affiliations

  • Karel CulikII
    • 1
  • Juhani Karhumäki
    • 2
  • Petri Salmela
    • 2
  1. 1.Department of Computer ScienceUniversity of South CarolinaColumbiaUSA
  2. 2.Department of Mathematics and, Turku Centre for Computer ScienceUniversity of TurkuTurkuFinland

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