• Title/Summary/Keyword: Absolute summability

Search Result 18, Processing Time 0.017 seconds

On the Summability of Infinite Series and Hüseyin Bor (무한급수의 총합 가능성과 후세인 보르에 관하여)

  • Lee, Jung Oh
    • Journal for History of Mathematics
    • /
    • v.30 no.6
    • /
    • pp.353-365
    • /
    • 2017
  • In general, there is summability among the mathematical tools that are the criterion for the convergence of infinite series. Many authors have studied on the summability of infinite series, the summability of Fourier series and the summability factors. Especially, $H{\ddot{u}}seyin$ Bor had published his important results on these topics from the beginning of 1980 to the end of 1990. In this paper, we investigate the minor academic genealogy of teachers and pupils from Fourier to $H{\ddot{u}}seyin$ Bor in section 2. We introduce the $H{\ddot{u}}seyin$ Bor's major results of the summability for infinite series from 1983 to 1997 in section 3. In conclusion, we summarize his research characteristics and significance on the summability of infinite series. Also, we present the diagrams of $H{\ddot{u}}seyin$ Bor's minor academic genealogy from Fourier to $H{\ddot{u}}seyin$ Bor and minor research lineage on the summability of infinite series.

A NEW PARANORMED SERIES SPACE USING EULER TOTIENT MEANS AND SOME MATRIX TRANSFORMATIONS

  • Gulec, G. Canan Hazar;Ilkhan, Merve
    • Korean Journal of Mathematics
    • /
    • v.28 no.2
    • /
    • pp.205-221
    • /
    • 2020
  • Paranormed spaces are important as a generalization of the normed spaces in terms of having more general properties. The aim of this study is to introduce a new paranormed space |𝜙z|(p) over the paranormed space ℓ(p) using Euler totient means, where p = (pk) is a bounded sequence of positive real numbers. Besides this, we investigate topological properties and compute the α-, β-, and γ duals of this paranormed space. Finally, we characterize the classes of infinite matrices (|𝜙z|(p), λ) and (λ, |𝜙z|(p)), where λ is any given sequence space.

On the study of Waterman with respect to Bounded Variation (유계변동과 관련된 Waterman의 연구에 대하여)

  • Kim Hwa-Jun
    • Journal for History of Mathematics
    • /
    • v.19 no.2
    • /
    • pp.115-124
    • /
    • 2006
  • Functions of bounded variation were discovered by Jordan in 1881 while working out the proof of Dirichlet concerning the convergence of Fourier series. Here, we investigate Waterman's study with respect to bounded variation and its application on a closed bounded interval. The value of his study is whether Dirichlet-Jordan theorem holds in which function classes or not and summability method is what modifies its Fourier coefficients to make resulting series converge to the associated function. We have a view that the directions of future research with respect to bounded variation are two things; one is to find the function spaces which are larger than HBV and smaller than ${\phi}BV$, and the other is to find a fields of applications.

  • PDF