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Initial segments of the degrees of unsolvability Part II: minimal degrees

Published online by Cambridge University Press:  12 March 2014

C. E. M. Yates*
Affiliation:
The University, Manchester, England

Extract

The first of this sequence of papers [21] surveyed the progress that has been made in embedding partially ordered sets as initial segments of the uncountable upper semilattice D of degrees of unsolvability. The principal concern of the present and subsequent parts will be with initial segments of the countable upper semilattice D (≦0(1)) of degrees ≦0(1); a summary appeared in [21].

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 1970

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