论文信息 - THE ω-ENUMERATION DEGREES

THE ω-ENUMERATION DEGREES

In the present paper we initiate the study of the partial ordering of the ω-enumeration degrees. This ordering is a semi-lattice which extends the semi-lattice of the enumeration degrees. The main results include a jump inversion theorem, a density theorem for the ω-enumeration degrees below the first jump of the least degree and the lack of minimal ω-enumeration degrees.

Ivan N. Soskov

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