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Irreducible, Singular, and Contiguous Degrees

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Algebra and Logic Aims and scope

We study structures of degrees of stronger algorithmic reducibilities inside the degrees of weaker algorithmic ones. Results in this area are reviewed for algorithmic reducibilities m-, 1-, tt-, wtt-, T-, e-, s-, Q-, and we formulate questions that are still not settled for these. A computably enumerable Q-degree which consists of one computably enumerable m-degree is constructed.

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  1. Kazan (VolgaRegion) FederalUniversity, ul.Kremlevskaya 18, Kazan, 420008, Russia

    I. I. Batyrshin

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Correspondence to I. I. Batyrshin.

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Translated from Algebra i Logika, Vol. 56, No. 3, pp. 275-299, May-June, 2017.

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Batyrshin, I.I. Irreducible, Singular, and Contiguous Degrees. Algebra Logic 56, 181–196 (2017). https://doi.org/10.1007/s10469-017-9439-4

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  • DOI: https://doi.org/10.1007/s10469-017-9439-4

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