### Lowness and Π₂⁰ nullsets

Rod Downey, Andre Nies, Rebecca Weber, and Liang Yu
Source: J. Symbolic Logic Volume 71, Issue 3 (2006), 1044-1052.

#### Abstract

We prove that there exists a noncomputable c.e. real which is low for weak 2-randomness, a definition of randomness due to Kurtz, and that all reals which are low for weak 2-randomness are low for Martin-Löf randomness.

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Permanent link to this document: http://projecteuclid.org/euclid.jsl/1154698590
Digital Object Identifier: doi:10.2178/jsl/1154698590
Mathematical Reviews number (MathSciNet): MR2251554
Zentralblatt MATH identifier: 1112.03040

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