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The degrees of hyperhyperimmune sets1
Published online by Cambridge University Press: 12 March 2014
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.
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- Copyright © Association for Symbolic Logic 1969
Footnotes
1
This research was supported by National Science Foundation grant GP 7421.
References
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