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Acta Informatica

, Volume 6, Issue 1, pp 95–108 | Cite as

Transformational methods and their application to complexity problems

  • Burkhard Monien
Article

Summary

The following results are proved by the use of transformabilities.
  1. 1.

    NTAPE (log n)=TAPE (log n)⇔There exists a j such that every language accepted by a nondeterministic one-way one-counter automaton is contained in Dj. (Dj is the family of all languages accepted by deterministic j-head two-way finite automata.)

     
  2. 2.

    NTAPE (n) =TAPE (n)⇔ There exists a j such that every language L ∉ {1}* accepted by a nondeterministic 5-head two-way finite automaton is contained in Dj.

     
  3. 3.

    \(\mathop U\limits_d\) TIME (nd=TAPE (log n)⇔ There exists a j such that every language accepted by a deterministic 1-head two-way pushdown automaton is contained in Dj.

     
  4. 4.

    f\(\mathop U\limits_d\) TIME (dn)=TAPE (n)⇔There exists a j such that every language L ⊂{1}* accepted by a deterministic 1-head two-way pushdown automaton is contained in Dj.

     
  5. 5.

    DjDj+1 for all j ε εN.

     

Keywords

Information System Operating System Data Structure Communication Network Information Theory 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • Burkhard Monien
    • 1
  1. 1.Universität Dortmund Abteilung InformatikDortmund-HombruchDeutschland

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