Locally Threshold Testable Languages of Infinite Words
نویسنده
چکیده
The class of nitely locally threshold testable !-languages is proved to be decidable relatively to the class of all regular !-languages. We apply this to the monadic second order theory of innnite word structures with successor function: it is decidable whether for a given monadic second-order formula there exists a rst-order formula with the same set of innnite word models.
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