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 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.
منابع مشابه
CDMTCS Research Report Series Difference Splittings of Recursively Enumerable Sets
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.
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عنوان ژورنال:
- J. UCS
دوره 3 شماره
صفحات -
تاریخ انتشار 1997