Fine Hierarchy of Regular w-Languages
نویسنده
چکیده
Abst rac t By applying descriptive set theory we get several facts on the fine structure of regular w-languages considered by K.Wagner. We present quite different, shorter proofs for main his results and get new results. Our description of the fine structure is new, very clear and automata-free. We prove also a closure property of the fine structure under Boolean operations. Our results demonstrate deep interconnections between descriptive set theory and theory of w-languages.
منابع مشابه
The Hausdorff-Kuratowski Hierarchy of omega-Regular Languages and a Hierarchy of Muller Automata
R. Barua, The Hausdorff-Kuratowski hierarchy of o-regular languages and a hierarchy of Muller automata, Theoretical Computer Science 96 (1992) 345-360. Given a finite alphabet Z, we give a simple characterization of those Gd subsets of Z” which are deterministic w-regular (i.e. accepted by Biichi automata) over Z and then characterize the w-regular languages in terms of these (rational) G6 sets...
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By applying descriptive set theory to the Wagner’s fine structure of regular ω-languages we get quite different proofs of his results and obtain new results. We give an automata-free description of the fine structure. We present also a simple property of a deterministic Muller automaton equivalent to the condition that the corresponding regular ω-language belongs to any given level of the fine ...
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