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ON CUPPING AND AHMAD PAIRS
Part of:
Computability and recursion theory
Published online by Cambridge University Press: 11 December 2022
Abstract
Working toward showing the decidability of the 
$\forall \exists $-theory of the 
${\Sigma ^0_2}$-enumeration degrees, we prove that no so-called Ahmad pair of 
${\Sigma ^0_2}$-enumeration degrees can join to 
${\mathbf 0}_e'$.
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- © The Author(s), 2022. Published by Cambridge University Press on behalf of The Association for Symbolic Logic
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