An example on existence of a 02n-computable family of total functions whose rogers semilattice contains an ideal without minimal elements

Authors

  • As. A. Issakhov
        45 53

Keywords:

n-computable numbering, 02n-computable family, computability relative to the oracle )1(0n, minimal numbering, Rogers semilattice, numerical equivalence, positive equivalence, ideal.

Abstract

We study computable families of total functions of any level of the Kleene-Mostowski hierarchy above level 1 and try to find elementary properties of the Rogers semilattices that are different from the properties of the classical Rogers semilattices for families of computable functions. It is known that on first level of the arithmetical hierarchy the Rogers semilattice of any computable family of total functions contains no ideal without minimal elements, [1]. In this article we show an example how to build 02n-computable family of total functions whose Rogers semilattice contains an ideal without minimal elements, n.

References

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How to Cite

Issakhov, A. A. (2015). An example on existence of a 02n-computable family of total functions whose rogers semilattice contains an ideal without minimal elements. International Journal of Mathematics and Physics, 6(1), 30–32. Retrieved from https://ijmph.kaznu.kz/index.php/kaznu/article/view/114