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On the upper semi-lattice of -degrees

Published online by Cambridge University Press:  22 January 2016

Juichi Shinoda*
Affiliation:
Department of Mathematics, Faculty of Science, Nagoya University
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S. C. Kleene developed the theory of recursive functionals of finite types in Kleene [5]. He proved that a set A of natural numbers is recursive in E if and only if A is hyperarithmetical, where E is the type 2 object defined by

Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 1980

References

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