Cofinality of normal ideals on P(λ), I
Abstract
Given an ordinal delta <= lambda and a cardinal theta <= kappa, an ideal J on Pkappa(lambda) is said to be [delta]<theta-normal if given Be in J for e in Ptheta(delta), the set of all a in Pkappa(lambda) such that a in Be for some e in P|a cap theta|(a cap delta) lies in J. We give necessary and sufficient conditions for the existence of such ideals and we describe the least one and we compute its cofinality.
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