The Book of L pp 147-156 | Cite as

Fixed and Stationary ω —Words and ω —Languages

  • Tom Head
  • Barbara Lando

Abstract

Explicit representations of the ω-words that are fixed (resp., stationary) relative to a function h: A -→ A* are given. A procedure is provided for constructing a concise expression for the fixed (resp., stationary) ω -language of such an h. The equivalence problem for fixed (resp., stationary) ω-languages of functions h & k: A -→ A* is shown to be decidable. The fundamental tool for this latter procedure is the recently developed algorithm of K. Culik II & T. Harju for deciding the ω -sequence equivalence problem.

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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • Tom Head
    • 1
  • Barbara Lando
    • 1
  1. 1.Department of Mathematical SciencesUniversity of AlaskaFairbanksUSA

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