Jump degrees of torsion-free abelian groups
نویسندگان
چکیده
We show, for each computable ordinal α and degree a > 0(α), the existence of a torsion-free abelian group with proper αth jump degree a.
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عنوان ژورنال:
- J. Symb. Log.
دوره 77 شماره
صفحات -
تاریخ انتشار 2012