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Bounding nonsplitting enumeration degrees. (English) Zbl 1131.03019
Ahmad has shown the existence of nonzero $$\Sigma^0_2$$ enumeration degrees, i.e., enumeration degrees below $${\mathbf 0}_e'$$ that are nonsplitting. The present paper shows that, in fact, every nonzero $$\Sigma^0_2$$ enumeration degree lies above such a degree.

##### MSC:
 03D30 Other degrees and reducibilities in computability and recursion theory
##### Keywords:
enumeration degree; nonsplitting
Full Text:
##### References:
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