Abstract
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.
Citation
Yue Yang. Liang Yu. "On the definable ideal generated by nonbounding c.e. degrees." J. Symbolic Logic 70 (1) 252 - 270, March 2005. https://doi.org/10.2178/jsl/1107298519
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