Collapsing Words vs. Synchronizing Words

  • D. S. Ananichev
  • M. V. Volkov
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2295)


We investigate the relationships between two types of words that have recently arisen in studying “black-box” versions of the famous Černý problem on synchronizing automata. Considering the languages formed by words of each of these types, we verify that one of them is regular while the other is not, thus showing that the two notions in question are different. We also discuss certain open problems concerning words of minimum length in these languages.


Minimum Length Regular Language Test Language Automaton Theory Transformation Semigroup 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • D. S. Ananichev
    • 1
  • M. V. Volkov
    • 1
  1. 1.Department of Mathematics and MechanicsUral State UniversityEkaterinburgRUSSIA

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