2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/153021Suppose 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 reflectionLogicSaturated filters at successors of singulars, weak reflection and yet another weak club principletext