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The degrees of hyperhyperimmune sets1

Published online by Cambridge University Press:  12 March 2014

Carl G. Jockusch Jr.
Carl G. Jockusch Jr.*
Affiliation:
University of Illinois
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Extract

In [5, Corollary 3.1] D. A. Martin characterized the degrees of the hyperhypersimple sets as those r.e. degrees a satisfying a′ = 0″. In the present paper we investigate the degrees of the hyperhyperimmune (h.h.i.) sets. We do not achieve a characterization of these degrees, but we do show that the condition a′ ≥ 0″ is sufficient, and the condition a′ ≥ 0′ is necessary, for a degree a to contain an h.h.i. set.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 34 , Issue 3 , 17 November 1969 , pp. 489 - 493
Copyright
Copyright © Association for Symbolic Logic 1969

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Footnotes

1

This research was supported by National Science Foundation grant GP 7421.

References

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