2 Leo Harrington And
نویسنده
چکیده
1. Introduction A set A of nonnegative integers is computably enumerable (c.e.), also called recursively enumerable (r.e.), if there is a computable method to list its elements.
منابع مشابه
The d . r . e . degrees are not dense S . BARRY COOPER LEO HARRINGTON ALISTAIR H . LACHLAN STEFFEN LEMPP
By constructing a maximal inco1nplete d.r.e. degree, the nondensity of the partial order of the d.r.e. degrees is established. An easy modification yields the nondensity of the n-r.e. degrees (n 2 2) and of the w-r.e, degrees,
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