Restricted jump interpolation in the d.c.e. degrees

نویسندگان

Carl G. Jockusch

Angsheng Li

چکیده

It is shown that for any 2-computably enumerable Turing degree l, any computably enumerable degree a, and any Turing degree s, if l′ = 0′, l < a, s ≥ 0′, and s is c.e. in a, then there is a 2-computably enumerable degree x with the following properties: (1) l < x < a, and (2) x′ = s.

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