Empty intervals in the enumeration degrees
نویسندگان
چکیده
We construct a Π2 enumeration degree which is a strong minimal cover.
منابع مشابه
Embedding countable partial orderings in the enumeration degrees and the ω-enumeration degrees
One of the most basic measures of the complexity of a given partially ordered structure is the quantity of partial orderings embeddable in this structure. In the structure of the Turing degrees, DT , this problem is investigated in a series of results: Mostowski [15] proves that there is a computable partial ordering in which every countable partial ordering can be embedded. Kleene and Post [10...
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ورودعنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 163 شماره
صفحات -
تاریخ انتشار 2012