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Computable categoricity of trees of finite height. (English) Zbl 1104.03026
The main result of this paper is a characterization of computably categorical trees of finite height. It is also proven that for such trees the computable categoricity is equivalent to the relative computable categoricity. It follows that if such a tree is not computably categorical then it has $$\omega$$ computably non-isomorphic isomorphic computable presentations. It is also proven that, for each natural number $$n\geq 1$$, there exists a computable tree which is $$\Delta_{n+1}^0$$-categorical but not $$\Delta_n^0$$-categorical.

##### MSC:
 03C57 Computable structure theory, computable model theory 03D45 Theory of numerations, effectively presented structures 03C35 Categoricity and completeness of theories
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