Sets with no subsets of higher weak truth-table degree

Patrizio Cintioli


We consider the weak truth-table reducibility < wtt and we prove the existence of wtt-introimmune sets in 02. This closes the gap on the existence of arithmetical r-introimmune sets for all the known reducibilities < r strictly contained in the Turing reducibility.

Słowa kluczowe: weak truth-table reducibility, introimmune sets.

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