Frequent universality criterion and densities

2018/07/11 by Romuald Ernst, Ernst, Romuald, Augustin Mouze +1
Mathematics · #Analytic and geometric function theory #Approximation Theory and Sequence Spaces #FOS: Mathematics #Functional Analysis (math.FA) #Mathematical functions and polynomials

paper · pdf · doi:10.48550/arxiv.1807.04171

openalex publication_date 2018/07/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We improve a recent result by giving the optimal conclusion possible both to the frequent universality criterion and the frequent hypercyclicity criterion using the notion of A-densities, where A refers to some weighted densities sharper than the natural lower density. Moreover we construct an operator which is logarithmically-frequently hypercyclic but not frequently hypercyclic.

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