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Splitting properties of n-c.e. enumeration degrees

Published online by Cambridge University Press:  12 March 2014

I. SH. Kalimullin
I. SH. Kalimullin*
Affiliation:
Chair of Algebra, Department of Mathematics, Kazan State University, 18 Kremlevskaya STR. 420008 Kazan, Russia, E-mail: Iskander.Kalimullin@ksu.ru
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Abstract

It is proved that if 1 < m < 2p ≤ n for some integer p then the elementary theories of posets of m-c.e. and n-c.e. e-degrees are distinct. It is proved also that the structures 〈2n, ≤, 〉 and 〈2n, ≤. P〉 are not elementary equivalent where P is the predicate P(a) = “a is a e-degree”.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 67 , Issue 2 , June 2002 , pp. 537 - 546
Copyright
Copyright © Association for Symbolic Logic 2002

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References

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