On strongly cube-free ω-words generated by binary morphisms

  • Juhani Karhumäki
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 117)


An ω-word is called strongly cube-free if it does not contain a subword of the form vvfirst(v), with v ≠ λ. We show that it is decidable whether a given morphism over a binary alphabet defines, when applied iteratively, a strongly cube-free ω-word. Moreover, an explicit and reasonably small upper bound for the number of iterations needed to be checked is given.


Decision Problem Basic Notion Symbolic Dynamic Springer Lecture Note Free Monoid 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1981

Authors and Affiliations

  • Juhani Karhumäki
    • 1
  1. 1.Department of MathematicsUniversity of TurkuTurkuFinland

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