We give a ΓΏrst-order coding without parameters of a copy of (N; +; Γ) in the computably enumerable weak truth table degrees. As a tool, we develop a theory of parameter deΓΏnable subsets.
Bounding computably enumerable degrees in the Ershov hierarchy
β Scribed by Angsheng Li; Guohua Wu; Yue Yang
- Publisher
- Elsevier Science
- Year
- 2006
- Tongue
- English
- Weight
- 219 KB
- Volume
- 141
- Category
- Article
- ISSN
- 0168-0072
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