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Related papers: Greedy bases in variable Lebesgue spaces

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Democracy functions of wavelet admissible bases are computed for weighted Orlicz Spaces in terms of its fundamental function. In particular, we prove that these bases are greedy if and only if the Orlicz space is a Lebesgue space. Also,…

History and Overview · Mathematics 2009-11-26 Maria de Natividade

We obtain Lebesgue-type inequalities for the greedy algorithm for arbitrary complete seminormalized biorthogonal systems in Banach spaces. The bounds are given only in terms of the upper democracy functions of the basis and its dual. We…

Functional Analysis · Mathematics 2017-09-18 P. M. Berná , O. Blasco , G. Garrigós , E. Hernández , T. Oikhberg

We show that for quasi-greedy bases in real Banach spaces the error of the thresholding greedy algorithm of order N is bounded by the best N-term error of approximation times a constant which depends on the democracy functions and the…

Functional Analysis · Mathematics 2011-11-17 Eugenio Hernández

We prove optimal embeddings for nonlinear approximation spaces in terms of weighted Lorentz sequence spaces, with the weights depending on the democracy functions of the basis. As applications we recover known embeddings for $N$-term…

Functional Analysis · Mathematics 2009-11-26 Gustavo Garrigós , Eugenio Hernández , Maria de Natividade

We show that for quasi-greedy bases in real or complex Banach spaces the error of the thresholding greedy algorithm of order N is bounded by the best N- term error of approximation times a function of N which depends on the democracy…

Functional Analysis · Mathematics 2012-07-05 Gustavo Garrigós , Eugenio Hernández , Timur Oikhberg

We present various estimates for the Lebesgue constants of the thresholding greedy algorithm, in the case of general bases in Banach spaces. We show the optimality of these estimates in some situations. Our results recover and slightly…

Functional Analysis · Mathematics 2016-06-22 Pablo M. Berná , Gustavo Garrigós , Óscar Blasco

In this paper we continue the study of Lebesgue-type inequalities for greedy algorithms. We introduce the notion of strong partially greedy Markushevich bases and study the Lebesgue-type parameters associated with them. We prove that this…

Functional Analysis · Mathematics 2020-02-11 Miguel Berasategui , Pablo M. Berná , Silvia Lassalle

We establish estimates for the Lebesgue parameters of the Chebyshev Weak Thresholding Greedy Algorithm in the case of general bases in Banach spaces. These generalize and slightly improve earlier results in [9], and are complemented with…

Functional Analysis · Mathematics 2018-11-13 Pablo M. Berná , Oscar Blasco , Gustavo Garrigós , Eugenio Hernández , Timur Oikhberg

We shall present a new characterization of greedy bases and 1-greedy bases in terms of certain functionals defined using distances to one dimensional subspaces generated by the basis. We also introduce a new property that unifies the…

Functional Analysis · Mathematics 2016-04-26 Pablo M. Berná , Óscar Blasco

We continue the study undertaken in \cite{GHN} of left democracy function $h_l(N)=\inf_{#\Lambda=N}\left\|\sum_{n\in \Lambda_N} x_n\right\| $ of an unconditional basis in a Banach space $X$. We provide an example of a basis with $h_l$…

Functional Analysis · Mathematics 2013-03-21 P. Wojtaszczyk

We continue the study of Lebesgue-type parameters for various greedy algorithms in quasi-Banach spaces. First, we introduce a parameter that can be used with the quasi-greedy parameter to obtain the exact growth of the Lebesgue parameter…

Functional Analysis · Mathematics 2025-08-28 Miguel Berasategui , Pablo M. Berná , Hung Viet Chu , Andrea García

In this paper we study Triebel-Lizorkin-type spaces with variable smoothness and integrability. We show that our space is well-defined, i.e., independent of the choice of basis functions and we obtain their atomic characterization. Moreover…

Functional Analysis · Mathematics 2016-01-14 Douadi Drihem

In this paper we study some estimates of norms in variable exponent Lebesgue spaces for a singular integral operators that are imaginary powers of the Laplace operator in $\R^n$. Using Mellin transform argument, from this estimates we…

Analysis of PDEs · Mathematics 2013-12-30 Alberto Fiorenza , Amiran Gogatishvili , Tengiz Kopaliani

We study the problem of improving the greedy constant or the democracy constant of a basis of a Banach space by renorming. We prove that every Banach space with a greedy basis can be renormed, for a given $\vare>0$, so that the basis…

Functional Analysis · Mathematics 2014-03-18 S. J. Dilworth , D. Kutzarova , E. Odell , Th. Schlumprecht , A. Zsák

We present new estimate for Hardy-type inequality in variable exponent Lebesgue spaces. More precisely, by imposing regularity assumptions on the exponent, we prove that the estimations can be reduced to the fixed exponents.

Functional Analysis · Mathematics 2017-03-09 Douadi Drihem

Two-weight norm estimates for the double Hardy transforms and strong fractional maximal functions are established in variable exponent Lebesgue spaces. Derived conditions are simultaneously necessary and sufficient in the case when the…

Functional Analysis · Mathematics 2010-07-07 Vakhtang Kokilashvili , Alexander Meskhi

We obtain convolution inequalities in Lebesgue and Lorentz spaces with power weights when the functions involved are assumed to be radially symmetric. We also present applications of these results to inequalities for Riesz potentials of…

Classical Analysis and ODEs · Mathematics 2013-08-01 Pablo L. De Nápoli , Irene Drelichman

Our aim is to study the modular inequalities for some operators, for example the Bergman projection acting on, in Lebesgue spaces with variable exponent. Under proper assumptions on the variable exponent, we prove that the modular…

Complex Variables · Mathematics 2019-11-12 Mitsuo Izuki , Takahiro Noi , Yoshihiro Sawano

Variable Muckenhoupt weights are considered in variable exponent Lebesgue spaces. Applications are given for polynomial approximation in these spaces. Boundedness of averaging operator is proved to gain a transference result. Almost all…

Classical Analysis and ODEs · Mathematics 2021-09-02 Ramazam Akgün

Let a vector-valued sublinear operator satisfy the size condition and be bounded on weighted Lebesgue spaces with variable exponent. Then we obtain its boundedness on weighted grand Herz-Morrey spaces with variable exponents. Next we…

Functional Analysis · Mathematics 2025-02-21 Shengrong Wang , Pengfei Guo , Jingshi Xu
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