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Related papers: An improved discrete Hardy inequality

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We characterize the weighted Hardy's inequalities for monotone functions in ${\mathbb R^n_+}.$ In dimension $n=1$, this recovers the classical theory of $B_p$ weights. For $n>1$, the result was only known for the case $p=1$. In fact, our…

Classical Analysis and ODEs · Mathematics 2007-05-23 Nicola Arcozzi , Sorina Barza , Josep L. Garcia-Domingo , Javier Soria

We prove an equivalence result between the validity of a pointwise Hardy inequality in a domain and uniform capacity density of the complement. This result is new even in Euclidean spaces, but our methods apply in general metric spaces as…

Analysis of PDEs · Mathematics 2026-03-19 Riikka Korte , Juha Lehrbäck , Heli Tuominen

We present simple proofs of a discrete fractional and non-fractional Hardy inequality, Our constants are explicit, but not optimal. In the class of power weights, we get a complete picture of when the non-fractional Hardy inequality holds,…

Functional Analysis · Mathematics 2025-06-18 Bartłomiej Dyda

We prove a generalization of a Hardy type inequality for negative exponents valid for non-negative functions defined on $(0,1]$. As an application we find the exact best possible range of $p$ such that $1<p\le q$ such that any…

Functional Analysis · Mathematics 2014-05-06 Eleftherios N. Nikolidakis

We consider Hardy inequalities in $I R^n$, $n \geq 3$, with best constant that involve either distance to the boundary or distance to a surface of co-dimension $k<n$, and we show that they can still be improved by adding a multiple of a…

Analysis of PDEs · Mathematics 2007-05-23 S. Filippas , V. Maz'ya , A. Tertikas

Let $A_i$ and $B_i$ be positive definite matrices for all $i=1,\cdots,m.$ It is shown that $$\left|\left|\sum_{i=1}^m(A_i^2\sharp…

Functional Analysis · Mathematics 2022-10-26 Shaima'a Freewan , Mostafa Hayajneh

The Hardy--Littlewood inequalities for $m$-linear forms on $\ell_{p}$ spaces are known just for $p>m$. The critical case $p=m$ was overlooked for obvious technical reasons and, up to now, the only known estimate is the trivial one. In this…

Functional Analysis · Mathematics 2017-10-24 Djair Paulino

In the context of Hardy inequalities for the fractional Laplacian $(-\Delta_{\mathbb{N}})^{\sigma}$ on the discrete half-line $\mathbb{N}$, we provide an optimal Hardy-weight $W^{\mathrm{op}}_{\sigma}$ for exponents…

Analysis of PDEs · Mathematics 2025-07-10 Ujjal Das , Rubén de la Fuente-Fernández

In the article we establish the Hardy-Littlewood inequality $ \pi (x + y) \leq \pi (x) + \pi (y) $. We also prove that the naturally ordered primes $p_1=2,p_2=3,p_3=5,p_4=7,\dots$ satisfy the inequality $ p_ {a + b}> p_a + p_b $ for all $a,…

Number Theory · Mathematics 2017-01-16 V. V. Miasoyedov

In this paper, we prove several new Hardy type inequalities (such as the weighted Hardy inequality, weighted Rellich inequality, critical Hardy inequality and critical Rellich inequality) for radial derivations (i.e., the derivation along…

Functional Analysis · Mathematics 2017-09-19 Van Hoang Nguyen

In this work, a generalization of the well known Bernoulli inequality is obtained by using the theory of discrete fractional calculus. As far as we know our approach is novel.

Classical Analysis and ODEs · Mathematics 2017-08-29 Rui A. C. Ferreira

Let $\Omega$ be a bounded domain of $\mathbb{R}^N$ whose boundary is a $\mathbb{C}^2$ compact manifolds. In the present paper we shall study a variational problem relating the weighted Hardy inequalities with sharp missing terms. As weights…

Analysis of PDEs · Mathematics 2020-08-13 Hiroshi Ando , Toshio Horiuchi

In this paper, we provide novel mean value estimates for exponential sums related to the extended main conjecture of Vinogradov's mean value theorem, by developing the Hardy-Littlewood circle method together with a refined shifting…

Number Theory · Mathematics 2025-06-25 Changkeun Oh , Kiseok Yeon

There has been recent interest in a hybrid form of the celebrated conjectures of Hardy-Littlewood and of Chowla. We prove that for any $k,\ell\ge1$ and distinct integers $h_2,\ldots,h_k,a_1,\ldots,a_\ell$, we have $$\sum_{n\leq…

Number Theory · Mathematics 2022-10-27 Jared Duker Lichtman , Joni Teräväinen

In this short note, we improve the famous Reid Inequality related to linear operators.

Functional Analysis · Mathematics 2017-04-25 Mohammed Hichem Mortad

Let $\Omega\subset{\mathbb R}^2$ be a bounded domain on which Hardy's inequality holds. We prove that $[\exp(u^2)-1]/\delta^2\in L^1(\Omega)$ if $u\in H^1_0(\Omega)$, where $\delta$ denotes the distance to $\partial\Omega$. The…

Analysis of PDEs · Mathematics 2025-07-04 Satyanad Kichenassamy

A short proof of the classic Hardy inequality is presented for $p$-norms with $p>1$. Along the lines of this proof a sharpened version is proved of a recent generalization of Hardy's inequality in the terminology of probability theory. A…

Probability · Mathematics 2022-06-28 Chris A. J. Klaassen

The objective of the present paper is to establish three Hardy-type inequalities in which the arithmetic mean over a sequence of non-negative real numbers is replaced by some weighted arithmetic mean over some nested subsets of the given…

Functional Analysis · Mathematics 2023-06-12 Ludovick Bouthat , Javad Mashreghi , Frédéric Morneau-Guérin

The existence of unimodular forms with small norms on sequence spaces is crucial in a variety of problems in modern analysis. We prove that the infimum of $\left\Vert A\right\Vert $ over all unimodular $d$-linear (complex or real) forms $A$…

Functional Analysis · Mathematics 2019-12-16 Nacib Gurgel Albuquerque , Lisiane Rezende

The Hardy--Littlewood inequality for complex homogeneous polynomials asserts that given positive integers $m\geq2$ and $n\geq1$, if $P$ is a complex homogeneous polynomial of degree $m$ on $\ell_{p}^{n}$ with $2m\leq p\leq\infty$ given by…

Functional Analysis · Mathematics 2015-10-08 Gustavo Araujo , Daniel Pellegrino