On the filter of computably enumerable supersets of an r-maximal set
نویسندگان
چکیده
We study the lter L (A) of computably enumerable supersets (modulo nite sets) of an r-maximal set A and show that, for some such set A, the property of being co nite in L (A) is still 0 3 -complete. This implies that for this A, there is no uniformly computably enumerable \tower" of sets exhausting exactly the coin nite sets in L (A).
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ورودعنوان ژورنال:
- Arch. Math. Log.
دوره 40 شماره
صفحات -
تاریخ انتشار 2001