On the sublinear functional associated to a family of invariant means
Tóm tắt
In this paper we give conditions under which we can obtain explicit analytic expressions of the fundamental sublinear functional PK of the family of means K=[G]∩J where [G] is a subset of G-invariant means, G a semigroup of operators on 1∞ and J a saturated set of means. Such conditions allow us to assure that [G]∩J≠φ. We characterize the set of the almost convergent sequences related to the family K by means of the same functional pK. We obtain also pK in terms of pJ when pJ is known. This allow us to give different expressions of the same functional pK when the family J changes and from which several examples are given.
Tài liệu tham khảo
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