On Context-Free Languages of Scattered Words

  • Zoltan Ésik
  • Satoshi Okawa
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7410)


It is known that if a Büchi context-free language (BCFL) consists of scattered words, then there is an integer n, depending only on the language, such that the Hausdorff rank of each word in the language is bounded by n. Every BCFL is a Muller context-free language (MCFL). In the first part of the paper, we prove that an MCFL of scattered words is a BCFL iff the rank of every word in the language is bounded by an integer depending only on the language. Then we establish operational characterizations of the BCFLs of well-ordered and scattered or well-ordered words.


Linear Ordering Order Type Syntactic Category Derivation Tree Tree Automaton 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Zoltan Ésik
    • 1
  • Satoshi Okawa
    • 2
  1. 1.Dept. of Computer ScienceUniversity of SzegedHungary
  2. 2.School of Computer Science and EngineeringUniversity of AizuJapan

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