Results 1 to 10 of about 21 (21)
Surjective isometries on Banach sequence spaces: A survey
Concrete Operators, 2022 In this survey, we present several results related to characterizing the surjective isometries on Banach sequence spaces. Our survey includes full proofs of these characterizations for the classical spaces as well as more recent results for combinatorial
Antunes Leandro, Beanland Kevin
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On the compactness and the essential norm of operators defined by infinite tridiagonal matrices
Concrete Operators, 2023 In this article, all sequences u{\boldsymbol{u}}, v{\boldsymbol{v}}, and w{\boldsymbol{w}} that define continuous and compact tridiagonal operators Tu,v,w{T}_{u,v,w} acting on the weighted sequence space lβ2{l}_{\beta }^{2} were characterized ...
Caicedo Alexander +2 more
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Alexandria Engineering Journal, 2022 The aim of this work is to give some fixed point results based on the technique of measure of noncompactness which extend the classical Darbo’s theorem.
Anupam Das +3 more
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Upper bounds of some matrix operators on binomial and Orlicz-binomial double sequence spaces
Scientific African, 2022 In this article, we introduce binomial double sequence space bk(α,β;γ,δ) (1≤k≤∞) and Orlicz-binomial double sequence space bφ(α,β;γ,δ), and obtain certain inclusion results related to these spaces.
Taja Yaying, Bipan Hazarika
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Approximation properties of tensor norms and operator ideals for Banach spaces
Open Mathematics, 2020 For a finitely generated tensor norm α\alpha , we investigate the α\alpha -approximation property (α\alpha -AP) and the bounded α\alpha -approximation property (bounded α\alpha -AP) in terms of some approximation properties of operator ideals.
Kim Ju Myung
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On uniform Kadec‐Klee properties and rotundity in generalized Cesàro sequence spaces
International Journal of Mathematics and Mathematical Sciences, Volume 2004, Issue 2, Page 91-97, 2004., 2004 We consider the generalized Cesàro sequence spaces defined by Suantai (2003) and consider it equipped with the Amemiya norm. The main purpose of this paper is to show that ces(p) equipped with the Amemiya norm is rotund and has uniform Kadec‐Klee property.
Narin Petrot, Suthep Suantai
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Contractive projections in Orlicz sequence spaces
Abstract and Applied Analysis, Volume 2004, Issue 2, Page 133-145, 2004., 2004 We characterize norm‐one complemented subspaces of Orlicz sequence spaces ℓM equipped with either Luxemburg or Orlicz norm, provided that the Orlicz function M is sufficiently smooth and sufficiently different from the square function. We measure smoothness of M using AC1 and AC2 classes introduced by Maleev and Troyanski in 1991, and the condition for
Beata Randrianantoanina
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On k‐nearly uniform convex property in generalized Cesàro sequence spaces
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 57, Page 3599-3607, 2003., 2003 We define a generalized Cesàro sequence space ces(p), where p = (pk) is a bounded sequence of positive real numbers, and consider it equipped with the Luxemburg norm. The main purpose of this paper is to show that ces(p) is k‐nearly uniform convex (k‐NUC) for k ≥ 2 when limn→∞infpn > 1. Moreover, we also obtain that the Cesàro sequence space cesp(where
Winate Sanhan, Suthep Suantai
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Some properties of Banach‐valued sequence spaces ℓp[X]
International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 5, Page 289-300, 2001., 2001 We discuss some properties of the Banach‐valued sequence space ℓp[X](1 ≤ p < ∞), the space of weakly p‐summable sequences on a Banach space X. For example, we characterize the reflexivity of ℓp[X], convergent sequences on ℓp[X], and compact subsets of ℓp[X].
Qingying Bu
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Characterizations of compact operators on ℓp−type fractional sets of sequences
Demonstratio Mathematica, 2019 Among the sets of sequences studied, difference sets of sequences are probably the most common type of sets. This paper considers some ℓp−type fractional difference sets via the gamma function.
Özger Faruk
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