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arXiv · 1807.04171

Frequent universality criterion and densities

Romuald Ernst·A Mouze
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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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Romuald Ernst, A Mouze. 2018-07-11. Frequent universality criterion and densities. https://arxiv.org/abs/1807.04171

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