On Transition Minimality of Bideterministic Automata

  • Hellis Tamm
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4588)


Bideterministic automata are deterministic automata with the property of their reversal automata also being deterministic. Bideterministic automata have previously been shown to be unique (up to an isomorphism) minimal NFAs with respect to the number of states. In this paper, we show that in addition to state minimality, bideterministic automata are also transition-minimal NFAs. However, as this transition minimality is not necessarily unique, we also present the necessary and sufficient conditions for a bideterministic automaton to be uniquely transition-minimal among NFAs. Furthermore, we show that bideterministic automata are transition-minimal ε-NFAs.


Transition Complexity Regular Language Loop Complexity Transition Minimality Deterministic Automaton 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Hellis Tamm
    • 1
  1. 1.Institute of Cybernetics, Akadeemia tee 21, 12618 TallinnEstonia

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