A functional analytic approach to Cesàro mean

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Abstract

We study the class P of positive linear functionals φ on L([1,∞)) for which φ(f)=α if [Formula presented]. The semigroup of translations f(x)↦f(rx) on L([1,∞)), where r∈[1,∞), plays a crucial role in the study of P. In particular, we give three different expressions of their extremal values, which can be considered main results of this paper. We also study linear functionals on l, the set of all real-valued bounded functions on natural numbers N, which extend Cesàro mean and give similar results about their extremal values, including a functional analytic proof of the classical result of Pólya.

Original languageEnglish
JournalIndagationes Mathematicae
DOIs
Publication statusPublished - 2019 Jan 1

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Linear Functionals
Natural number
Semigroup
Class

Keywords

  • Cesàro mean
  • Density measures
  • Pólya density
  • Stone–Čech compactification

ASJC Scopus subject areas

  • Mathematics(all)

Cite this

A functional analytic approach to Cesàro mean. / Kunisada, Ryoichi.

In: Indagationes Mathematicae, 01.01.2019.

Research output: Contribution to journalArticle

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