Cofinality of the nonstationary ideal
Abstract
We show that the reduced cofinality of the nonstationary ideal NSkappa on a regular uncountable cardinal kappa may be less than its cofinality, where the reduced cofinality of NSkappa is the least cardinality of any family F of nonstationary subsets of kappa such that every nonstationary subset of kappa can be covered by less than many members of F.
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