A Short Note on Infinite Union/Intersection of Omega Regular Languages
نویسنده
چکیده
Themost impressivenon-star-freeproperty, firstpointedoutbyWolper [Wol83], “p holds at every even moment” (we in what follows refer to it as P(2)) cannot be expressed by any LTL [Pnu77] formula. As a consequence, numerous extensions or LTL have been presented, such as ETL [VW94], QLTL [SVW87], RLTL [LS07], linear-time μTL [BB87] etc, and all of them are known to be as expressive as (nondeterministic) Büchi automata [Büc62], alternatively,ω-regular languages. Indeed,L (P(2)) = ⋂ k∈NL (X p), and this indicates that star-free languages are not closed under infinite intersection. It naturally enlightens us to make one step ahead, and now the question of interest is:
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عنوان ژورنال:
- CoRR
دوره abs/1603.05426 شماره
صفحات -
تاریخ انتشار 2016