Algebra and Logic

, Volume 43, Issue 2, pp 94–101

# Relatively Hyperimmune Relations on Structures

• S. S. Goncharov
• C. F. McCoy
• J. F. Knight
• V. S. Harizanov
Article

## Abstract

Let $${\mathcal{A}}$$ be a computable structure and let R be an additional relation on its domain. We establish a necessary and sufficient condition for the existence of an isomorphic copy $${\mathcal{B}}$$ of $${\mathcal{A}}$$ such that the image of R$$\neg R$$ is h-simple (h-immune) relative to $${\mathcal{B}}$$.

computable structure relatively hyperimmune relation relatively hypersimple relation

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## Authors and Affiliations

• S. S. Goncharov
• 1
• C. F. McCoy
• 2
• J. F. Knight
• 3
• V. S. Harizanov
• 4
1. 1.Institute of Mathematics SB RASNovosibirskRussia