Index sets in the arithmetical Hierarchy
نویسندگان
چکیده
منابع مشابه
The Logic of Arithmetical Hierarchy
Dzhaparidze, G., The logic of arithmetical hierarchy, Annals of Pure and Applied Logic 66 (1994) 89-112. Formulas of the propositional modal language with the unary modal operators 0, H,, B,, Zz, I!!,, are considered as schemata of sentences of arithmetic (PA), where q A is interpreted as (a formalization of) “A is PA-provable”, X,,A as “A is PA-equivalent to a &-sentence” and &,A as “A is PA-e...
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 1988
ISSN: 0168-0072
DOI: 10.1016/0168-0072(88)90023-1