Characterizing the Regular Languages by Nonforgetting Restarting Automata

  • Norbert Hundeshagen
  • Friedrich Otto
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6795)


We study nonforgetting R- and nonforgetting deterministic RR-automata of window size one, that is, nf-R(1)- and det-nf-RR(1)-automata. Our main result shows that the monotone variants of these two types of restarting automata characterize the regular languages. On the other hand, we prove that already the non-monotone deterministic nonforgetting R(1)-automata accept a class of languages that is incomparable to the class of semi-linear languages with respect to inclusion, but that properly includes the class of languages that are accepted by globally deterministic cooperating distributed systems of stateless deterministic R(1)-automata.


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© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Norbert Hundeshagen
    • 1
  • Friedrich Otto
    • 1
  1. 1.Fachbereich Elektrotechnik/InformatikUniversität KasselKasselGermany

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