Acta Informatica

, Volume 27, Issue 2, pp 179–191 | Cite as

HDTOL matching of computations of multitape automata

  • Karel CulikII
  • Juhani Karhumäki


We discuss the technique for testing the equivalence of two deterministic automata by constructing a language that matches the computations of two equivalent automata on the same input word. Specifically, we propose to use HDTOL languages that are powerful enough to match computations of many equivalent deterministic multitape automata, and at the same time, have nice decidable properties. Using this new technique of HDTOL matching, we show that the inclusion problem between an arbitrary deterministic multitape automaton and a simple one is decidable in both directions. Further, we show that the equivalence for a restricted class of transducers based on deterministic multitape automata is decidable.


Information System Operating System Data Structure Communication Network Information Theory 
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Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • Karel CulikII
    • 1
  • Juhani Karhumäki
    • 2
  1. 1.Department of Computer ScienceUniversity of South CarolinaColumbiaUSA
  2. 2.Department of MathematicsUniversity of TurkuTurkuFinland

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