The Least ∑-jump Inversion Theorem for n-families
نویسندگان
چکیده
Studying the Σ-reducibility of families introduced by [Kalimullin and Puzarenko 2009] we show that for every set X T ∅′ there is a family of sets F which is the Σ-least countable family whose Σ-jump is Σ-equivalent to X ⊕X. This fact will be generalized for the class of n-families (families of families of . . . of sets).
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ورودعنوان ژورنال:
- J. UCS
دوره 23 شماره
صفحات -
تاریخ انتشار 2017