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A high noncuppable \({\Sigma^0_2}\) e-degree

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Abstract

We construct a \({\Sigma^0_2}\) e-degree which is both high and noncuppable. Thus demonstrating the existence of a high e-degree whose predecessors are all properly \({\Sigma^0_2}\).

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  1. Dipartimento di Scienze Matematiche ed Informatiche “Roberto Magari”, Pian dei Mantellini 44, 53100, Siena, Italy

    Matthew B. Giorgi

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  1. Matthew B. Giorgi
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Correspondence to Matthew B. Giorgi.

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Giorgi, M.B. A high noncuppable \({\Sigma^0_2}\) e-degree. Arch. Math. Logic 47, 181–191 (2008). https://doi.org/10.1007/s00153-006-0021-3

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  • DOI: https://doi.org/10.1007/s00153-006-0021-3

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