Conjunctive Grammars Can Generate Non-regular Unary Languages

  title={Conjunctive Grammars Can Generate Non-regular Unary Languages},
  author={Artur Jeż},
  booktitle={International Conference on Developments in Language Theory},
  • Artur Jeż
  • Published in
    International Conference on…
    1 June 2008
  • Linguistics
Conjunctive grammars were introduced by A. Okhotin in [1] as a natural extension of context-free grammars with an additional operation of intersection in the body of any production of the grammar. Several theorems and algorithms for context-free grammars generalize to the conjunctive case. Still some questions remained open. A. Okhotin posed nine problems concerning those grammars. One of them was a question, whether a conjunctive grammar over unary alphabet can generate only regular languages… 

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