On Some Recognizable Picture-Languages

  title={On Some Recognizable Picture-Languages},
  author={Klaus Reinhardt},
  • K. Reinhardt
  • Published in MFCS 24 August 1998
  • Computer Science
We show that the language of pictures over {a, b}, where all occurring b's are connected is recognizable, which solves an open problem in [Mat98]. We generalize the used construction to show that monocausal deterministically recognizable picture languages are recognizable, which is surprisingly nontrivial. Furthermore we show that the language of pictures over {a, b}, where the number of a's is equal to the number of b's is nonuniformly recognizable. 

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