CDMTCS Research Report Series Difference Splittings of Recursively Enumerable Sets
نویسنده
چکیده
We study here the degree-theoretic structure of set-theoretical splittings of recursively enumerable (r.e.) sets into differences of r.e. sets. As a corollary we deduce that the ordering of wtt–degrees of unsolvability of differences of r.e. sets is not a distributive semilattice and is not elementarily equivalent to the ordering of r.e. wtt–degrees of unsolvability.
منابع مشابه
Difference Splittings of Recursively Enumerable Sets
We study here the degree-theoretic structure of set-theoretical splittings of recursively enumerable r.e. sets into diierences of r.e. sets. As a corollary we deduce that the ordering of wttdegrees of unsolvability of diierences of r.e. sets is not a distributive semilattice and is not elementarily equivalent to the ordering of r.e. wttdegrees of unsolvability.
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