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Noncappable enumeration degrees below 0e′

Published online by Cambridge University Press:  12 March 2014

S. Barry Cooper  and
Andrea Sorbi
S. Barry Cooper
Affiliation:
School of Mathematics, University of Leeds, LS2 9JT, England, E-mail: s.b.cooper@leeds.ac.uk
Andrea Sorbi
Affiliation:
Department of Mathematics, University of Siena, 53100 Siena, Italy, E-mail: sorbi@unisi.it
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Abstract

We prove that there exists a noncappable enumeration degree strictly below 0e′.

Keywords

Enumeration operatorenumeration degreeΣ20-set
Type
Research Article
Information
The Journal of Symbolic Logic , Volume 61 , Issue 4 , December 1996 , pp. 1347 - 1363
Copyright
Copyright © Association for Symbolic Logic 1996

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References

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