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Degrees which do not bound minimal degrees
The high/low hierarchy respects the ordering of degrees, and so we can expect to find properties of order which are possessed by all degrees in a given hierarchy class. Such properties can also be found for classes of the generalized high/low hierarchy even though that hierarchy does not respect the ordering of the degrees. For example, Jockusch and Posner [4], extending a result of Cooper [l],...
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ژورنال
عنوان ژورنال: Annals of Mathematical Logic
سال: 1972
ISSN: 0003-4843
DOI: 10.1016/0003-4843(72)90006-x