## Notre Dame Journal of Formal Logic

### Normal Numbers and Limit Computable Cantor Series

#### Abstract

Given any oracle, $A$, we construct a basic sequence $Q$, computable in the jump of $A$, such that no $A$-computable real is $Q$-distribution-normal. A corollary to this is that there is a $\Delta^{0}_{n+1}$ basic sequence with respect to which no $\Delta^{0}_{n}$ real is distribution-normal. As a special case, there is a limit computable sequence relative to which no computable real is distribution-normal.

#### Article information

Source
Notre Dame J. Formal Logic, Volume 58, Number 2 (2017), 215-220.

Dates
Accepted: 21 November 2014
First available in Project Euclid: 22 March 2017

https://projecteuclid.org/euclid.ndjfl/1490148081

Digital Object Identifier
doi:10.1215/00294527-2017-0004

Mathematical Reviews number (MathSciNet)
MR3634977

Zentralblatt MATH identifier
06751299

Subjects
Primary: 03D28: Other Turing degree structures
Secondary: 03D80: Applications of computability and recursion theory

#### Citation

Beros, Achilles; Beros, Konstantinos. Normal Numbers and Limit Computable Cantor Series. Notre Dame J. Formal Logic 58 (2017), no. 2, 215--220. doi:10.1215/00294527-2017-0004. https://projecteuclid.org/euclid.ndjfl/1490148081

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