Relative enumerability in the di erence hierarchy
نویسندگان
چکیده
We show that the intersection of the class of 2-REA degrees with that of the !-r.e. degrees consists precisely of the class of d.r.e. degrees. We also include some applications and show that there is no natural generalization of this result to higher levels of the REA hierarchy.
منابع مشابه
Orr Sommerfeld Solver Using Mapped Finite Di?erence Scheme for Plane Wake Flow
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