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The distribution of the generic recursively enumerable degrees

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In this paper we investigate problems about densities ofe-generic,s-generic andp-generic degrees. We, in particular, show that allp-generic degrees are non-branching, which answers an open question by Jockusch who asked: whether alls-generic degrees are non-branching and refutes a conjecture of Ingrassia; the set of degrees containing r.e.p-generic sets is the same as the set of r.e. degrees containing an r.e. non-autoreducible set.

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Authors and Affiliations

  1. Department of Mathematics, Nanjing University, 210008, Nanjing, Peoples' Republic of China

    Ding Decheng

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  1. Ding Decheng
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This research was supported by a grant of the Stiftung Volkswagenwerk

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Decheng, D. The distribution of the generic recursively enumerable degrees. Arch Math Logic 32, 113–135 (1992). https://doi.org/10.1007/BF01269953

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  • DOI: https://doi.org/10.1007/BF01269953

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