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RT2 2 does not imply WKL0

Published online by Cambridge University Press:  12 March 2014

Jiayi Liu
Affiliation:
Department of Mathematics, Central South University, South Campus, South Dormitory No. 6 Room 619, Changsha, 410083, China, E-mail: g.jiayi.liu@gmail.com
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Abstract

We prove that by showing that for any set C not of PA-degree and any set A, there exists an infinite subset G of A or such that GC is also not of PA-degree.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2012

References

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[8] Simpson, Stephen G., Subsystems of second order arithmetic. Perspectives in Mathematical Logic. Springer-Verlag, Berlin, 1999.CrossRefGoogle Scholar
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RT2 2 does not imply WKL0
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