## Journal of Symbolic Logic

### Array nonrecursiveness and relative recursive enumerability

Mingzhong Cai

#### Abstract

In this paper we prove that a degree a is array nonrecursive (ANR) if and only if every degree ba is r.e. in and strictly above another degree (RRE). This result will answer some questions in [ASDWY]. We also deduce an interesting corollary that every n-REA degree has a strong minimal cover if and only if it is array recursive.

#### Article information

Source
J. Symbolic Logic, Volume 77, Issue 1 (2012), 21-32.

Dates
First available in Project Euclid: 20 January 2012

https://projecteuclid.org/euclid.jsl/1327068689

Digital Object Identifier
doi:10.2178/jsl/1327068689

Mathematical Reviews number (MathSciNet)
MR2951627

Zentralblatt MATH identifier
1269.03044

Subjects
Primary: 03D28: Other Turing degree structures

#### Citation

Cai, Mingzhong. Array nonrecursiveness and relative recursive enumerability. J. Symbolic Logic 77 (2012), no. 1, 21--32. doi:10.2178/jsl/1327068689. https://projecteuclid.org/euclid.jsl/1327068689

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