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On a problem of Cooper and Epstein

Published online by Cambridge University Press:  12 March 2014

Shamil Ishmukhametov
Shamil Ishmukhametov*
Affiliation:
42 Tolstoy St., Dept. Math., Ulyanovsk State University, 432700, Ulyanovsk, Russia, E-mail: ishm@vens.ru
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Abstract

In “Bounding minimal degrees by computably enumerable degrees” by A. Li and D. Yang, (this Journal, [1998]), the authors prove that there exist non-computable computably enumerable degrees c > a > 0 such that any minimal degree m being below c is also below a. We analyze the proof of their result and show that the proof contains a mistake. Instead we give a proof for the opposite result.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 68 , Issue 1 , March 2003 , pp. 52 - 64
Copyright
Copyright © Association for Symbolic Logic 2003

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References

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