Low, Superlow, and Superduperlow Sets: An Exposition of a Known But Not Well-Known Result

William Gasarch

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arXiv · 1501.02299

Low, Superlow, and Superduperlow Sets: An Exposition of a Known But Not Well-Known Result

William Gasarch

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Abstract

A set is low if A' \le_T HALT. A set is superlow if A' \le_tt HALT. A set is superduperlow if A' \le_btt HALT. While it was known that any superduperlow is decidable it does not seem to be well known. We include two unpublished proofs of this result: One from Carl Jockush and one from Frank Stephan.

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BibTeX RIS

William Gasarch. 2015-01-10. Low, Superlow, and Superduperlow Sets: An Exposition of a Known But Not Well-Known Result. https://arxiv.org/abs/1501.02299

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