On the degree of ambiguity of finite automata

  • Andreas Weber
  • Helmut Seidl
Part of the Lecture Notes in Computer Science book series (LNCS, volume 233)


We show that the degree of ambiguity of a nondeterministic finite automaton (NFA) with n states, if finite, is not greater than 2n·log2n + c1·n (c1 ≅ 2.0566). We present an algorithm which decides in polynomial time whether the degree of ambiguity of a NFA is finite or not. Additionally, the authors obtain in [14] a corresponding upper bound for the finite valuedness of a normalized finite transducer (NFT), and also a polynomial-time algorithm which decides whether the valuedness of a NFT is finite or not.


Polynomial Time Short Form Sequential Machine Input String Fixed Integer 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • Andreas Weber
    • 1
  • Helmut Seidl
    • 1
  1. 1.Fachbereich InformatikJ. W. Goethe-UniversitätFrankfurt am MainWest Germany

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