Weak Computability and Representation of Real Numbers
نویسندگان
چکیده
Analogous to Ershov’s hierarchy for ∆2-subsets of natural numbers we discuss the similar hierarchy for recursively approximable real numbers. Namely, we define the k-computability for natural number k and f -computability for function f . We will show that these notions are not equivalent for different representations of real numbers based on Cauchy sequence, Dedekind cut and binary expansion.
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