Symmetric Enumeration Reducibility
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چکیده
منابع مشابه
Constructing Minimal Pairs of Degrees
We prove that there exist sets of natural numbers A and B such that A and B form a minimal pair with respect to Turing reducibility, enumeration reducibility, hyperarithmetical reducibility and hyperenumer-ation reducibility. Relativized versions of this result are presented as well. 1. Introduction In the present paper we consider four kinds of reducibilities among sets of natural numbers: Tur...
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تاریخ انتشار 2005