English
Related papers

Related papers: An improved Copson inequality

200 papers

In this current work, we revisit the recent improvement of the discrete Hardy's inequality in one dimension and establish an extended improved discrete Hardy's inequality with its optimality. We also study one-dimensional discrete Copson's…

Functional Analysis · Mathematics 2023-04-18 Bikram Das , Atanu Manna

Using a method of factorization and by introducing a generalized discrete Dirichlet's Laplacian matrix $(-\Delta_{\Lambda})$, we establish an extended improved discrete Hardy's inequality and Rellich inequality in one dimension. We prove…

Functional Analysis · Mathematics 2024-03-27 Bikram Das , Atanu Manna

We improve the classical discrete Hardy inequality \begin{equation*}\label{1} \sum _{{n=1}}^{\infty }a_{n}^{2}\geq \left({\frac {1}{2}}\right)^{2} \sum _{{n=1}}^{\infty }\left({\frac {a_{1}+a_{2}+\cdots +a_{n}}{n}}\right)^{2},…

Spectral Theory · Mathematics 2016-12-20 Matthias Keller , Yehuda Pinchover , Felix Pogorzelski

In this paper we consider a weighted version of one dimensional discrete Hardy's Inequality on half-line with power weights of the form $n^\alpha$. Namely we consider: \begin{equation} \sum_{n=1}^\infty |u(n)-u(n-1)|^2 n^\alpha \geq…

Functional Analysis · Mathematics 2022-05-20 Shubham Gupta

Let $(\lambda_n)_{n \geq 1}$ be a non-negative sequence with $\lambda_1>0$ and let $\Lambda_n=\sum^n_{i=1}\lambda_i$. We study the following Copson inequality for $0<p<1$, $L>p$, \begin{align*} \sum^{\infty}_{n=1}\left (\frac 1{\Lambda_n}…

Classical Analysis and ODEs · Mathematics 2018-06-21 Peng Gao , Huayu Zhao

We extend the classical Copson's inequalities so that the values of parameters involved go beyond what is currently known.

Classical Analysis and ODEs · Mathematics 2012-01-05 Peng Gao

For the functions $f$, which can be represented in the form of the convolution $f(x)=\frac{a_{0}}{2}+\frac{1}{\pi}\int\limits_{-\pi}^{\pi}\sum\limits_{k=1}^{\infty}e^{-\alpha k^{r}}\cos(kt-\frac{\beta\pi}{2})\varphi(x-t)dt$,…

Classical Analysis and ODEs · Mathematics 2020-05-29 A. S. Serdyuk , T. A. Stepaniuk

Usually when solving differential or difference equations via series solutions one encounters divergent series in which the coefficients grow like a factorial. Surprisingly, in the $q$-world the $n$th coefficient is often of the size…

Classical Analysis and ODEs · Mathematics 2024-03-05 Nalini Joshi , Adri Olde Daalhuis

We characterize a four-weight inequality involving the Hardy operator and the Copson operator. More precisely, given $p_1, p_2, q_1, q_2 \in (0, \infty)$, we find necessary and sufficient conditions on nonnegative measurable functions $u_1,…

Functional Analysis · Mathematics 2022-03-02 Amiran Gogatishvili , Luboš Pick , Tuğçe Ünver

Koksma's equidistribution theorem from 1935 states that for Lebesgue almost every $\alpha>1$, the fractional parts of the geometric progression $(\alpha^{n})_{n\geq1}$ are equidistributed modulo one. In the present paper we sharpen this…

Number Theory · Mathematics 2020-10-21 Christoph Aistleitner , Simon Baker , Niclas Technau , Nadav Yesha

Although the Hardy inequality corresponding to one quadratic singularity, with optimal constant, does not admit any extremal function, it is well known that such a potential can be improved, in the sense that a positive term can be added to…

Analysis of PDEs · Mathematics 2012-12-06 Jean Dolbeault , Bruno Volzone

Many classical geometric inequalities on functionals of convex bodies depend on the dimension of the ambient space. We show that this dimension dependence may often be replaced (totally or partially) by different symmetry measures of the…

Metric Geometry · Mathematics 2014-12-11 René Brandenberg , Stefan König

We consider strictly increasing sequences $\left(a_{n}\right)_{n \geq 1}$ of integers and sequences of fractional parts $\left(\left\{a_{n} \alpha\right\}\right)_{n \geq 1}$ where $\alpha \in \mathbb{R}$. We show that a small additive…

Number Theory · Mathematics 2016-08-25 Christoph Aistleitner , Gerhard Larcher

It is not surprising that one should expect that the degree of constrained (shape preserving) approximation be worse than the degree of unconstrained approximation. However, it turns out that, in certain cases, these degrees are the same.…

Classical Analysis and ODEs · Mathematics 2019-01-15 K. A. Kopotun , D. Leviatan , I. A. Shevchuk

For $n$ positive numbers ($a_k$, $1\leq k \leq n$), enhanced inequalities about the arithmetic mean ($A_n \equiv \frac{\sum_ka_k}{n}$) and the geometric mean ($G_n\equiv \sqrt[n]{\Pi_ka_k}$) are found if some numbers are known, namely,…

General Mathematics · Mathematics 2020-08-11 Fang Dai , Li-Gang Xia

We show that any $d$-Ahlfors regular subset of $\mathbb{R}^{n}$ supporting a weak $(1,d)$-Poincar\'e inequality with respect to surface measure is uniformly rectifiable.

Classical Analysis and ODEs · Mathematics 2020-09-10 Jonas Azzam

In this paper we established a new Simpson type conformable fractional integral equality for convex functions. Based on this identity, some results related to Simpson-like type inequalities are obtained. These results are then applied to…

Classical Analysis and ODEs · Mathematics 2024-09-05 Zeynep Şanlı

We solve a long-standing open problem in theory of weighted inequalities concerning iterated Copson operators. We use a constructive approximation method based on a new discretization principle that is developed here. In result, we…

Functional Analysis · Mathematics 2019-05-06 Martin Křepela , Luboš Pick

We prove a quantitative version of the Duffin-Schaeffer conjecture with an almost sharp error term. Precisely, let $\psi:\mathbb{N}\to[0,1/2]$ be a function such that the series $\sum_{q=1}^\infty \varphi(q)\psi(q)/q$ diverges. In addition,…

Number Theory · Mathematics 2024-09-23 Dimitris Koukoulopoulos , James Maynard , Daodao Yang

Let $0<s<1$ and $p>1$ be such that $ps<N$. Assume that $\Omega$ is a bounded domain containing the origin. Staring from the ground state inequality by R. Frank and R. Seiringer we obtain: 1- The following improved Hardy inequality for $p\ge…

Analysis of PDEs · Mathematics 2018-12-11 Boumediene Abdellaoui , Rachid Bentifour
‹ Prev 1 2 3 10 Next ›