منابع مشابه
Relative Randomness and Cardinality
A set B ⊆ N is called low for Martin-Löf random if every Martin-Löf random set is also Martin-Löf random relative to B. We show that a ∆2 set B is low for Martin-Löf random iff the class of oracles which compress less efficiently than B, namely the class C = {A | ∀n K(n) ≤ K(n)} is countable (where K denotes the prefix free complexity and ≤ denotes inequality modulo a constant). It follows that...
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ژورنال
عنوان ژورنال: Annals of Pure and Applied Logic
سال: 1993
ISSN: 0168-0072
DOI: 10.1016/0168-0072(93)90209-v