Saturated filters at successors of singulars, weak reflection and yet another weak club principle
Abstract
Suppose that lambda is the successor of a singular cardinal mu whose cofinality is an uncountable cardinal kappa. We give a sufficient condition that the club filter of lambda concentrating on the points of cofinality kappa is not lambda+-saturated. The condition is phrased in terms of a notion that we call weak reflection. We discuss various properties of weak reflection
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