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Bounding and nonbounding minimal pairs in the enumeration degrees

  • S. Barry Cooper (a1), Angsheng Li (a2), Andrea Sorbi (a3) and Yue Yang (a4)

Abstract

We show that every nonzero Δ20, e-degree bounds a minimal pair. On the other hand, there exist Σ20, e-degrees which bound no minimal pair.

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Bounding and nonbounding minimal pairs in the enumeration degrees

  • S. Barry Cooper (a1), Angsheng Li (a2), Andrea Sorbi (a3) and Yue Yang (a4)

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