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Isomorphisms between HEO and HROE, ECF and ICFE

Published online by Cambridge University Press:  12 March 2014

Marc Bezem*
Affiliation:
Korenbloemstraat 44, 3551 Gn Utrecht, The, Netherlands

Abstract

In this paper it will be shown that HEO and HROE are isomorphic with respect to extensional equality. This answers a question of Troelstra [T, 2.4.12, p. 128]. The main problem is to extend effective operations to a larger domain. This will be achieved by a modification of the proof of the continuity of effective operations. Following a suggestion of A. S. Troelstra, similar results were obtained for ECF(U) and ICFE(U), where U is any universe of functions closed under “recursive in”.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1985

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References

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