Level Two of the Quantifier Alternation Hierarchy Over Infinite Words
نویسندگان
چکیده
منابع مشابه
Quantifier Alternation for Infinite Words
We investigate the expressive power of the quantifier alternation hierarchy of first-order logic over words. This hierarchy includes the classes Σi (sentences having at most i blocks of quantifiers starting with an ∃) and BΣi (Boolean combinations of Σi sentences). So far, this expressive power has been effectively characterized for the lower levels only. Recently, a breakthrough was made over ...
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ژورنال
عنوان ژورنال: Theory of Computing Systems
سال: 2017
ISSN: 1432-4350,1433-0490
DOI: 10.1007/s00224-017-9801-x