On the definable ideal generated by the plus cupping c.e. degrees
نویسندگان
چکیده
In this paper we will prove that the plus cupping degrees generate a definable ideal on c.e. degrees different from other ones known so far, thus answer a question asked by A. Li and Yang.
منابع مشابه
On the definable ideal generated by nonbounding c.e. degrees
Let [NB]1 denote the ideal generated by nonbounding c.e. degrees and NCup the ideal of noncuppable c.e. degrees. We show that both [NB]1 ∩ NCup and the ideal generated by nonbounding and noncuppable degrees are new, in the sense that they are different from M, [NB]1 and NCup — the only three known definable ideals so far.
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ورودعنوان ژورنال:
- Arch. Math. Log.
دوره 46 شماره
صفحات -
تاریخ انتشار 2007