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Comparing the degrees of enumerability and the closed Medvedev degrees

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 نشر من قبل Paul Shafer
 تاريخ النشر 2018
  مجال البحث
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We compare the degrees of enumerability and the closed Medvedev degrees and find that many situations occur. There are nonzero closed degrees that do not bound nonzero degrees of enumerability, there are nonzero degrees of enumerability that do not bound nonzero closed degrees, and there are degrees that are nontrivially both degrees of enumerability and closed degrees. We also show that the compact degrees of enumerability exactly correspond to the cototal enumeration degrees.



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