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arXiv · 1601.08237

The omega-inequality problem for concatenation hierarchies of star-free languages

J. Almeida·O. Klíma·M. Kunc
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Abstract

The problem considered in this paper is whether an inequality of omega-terms is valid in a given level of a concatenation hierarchy of star-free languages. The main result shows that this problem is decidable for all (integer and half) levels of the Straubing-Th\'erien hierarchy.

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J. Almeida, O. Klíma, M. Kunc. 2016-01-29. The omega-inequality problem for concatenation hierarchies of star-free languages. https://doi.org/10.1515/forum-2016-0028

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