{"title":"A lower bound for the Lebesgue constant of the Morrow–Patterson points","authors":"Tomasz Beberok","doi":"10.1016/j.jat.2025.106191","DOIUrl":null,"url":null,"abstract":"<div><div>The study of interpolation nodes and their associated Lebesgue constants is a cornerstone of numerical analysis, directly influencing the stability and accuracy of polynomial approximations. In this paper, we examine the Morrow–Patterson points, a specific set of interpolation nodes introduced to construct cubature formulas with the minimal number of points in a square for a fixed degree <span><math><mi>n</mi></math></span>. We prove that their Lebesgue constant has minimal rate of growth of at least <span><math><mrow><mi>O</mi><mrow><mo>(</mo><msup><mrow><mi>n</mi></mrow><mrow><mn>2</mn></mrow></msup><mo>)</mo></mrow></mrow></math></span>.</div></div>","PeriodicalId":54878,"journal":{"name":"Journal of Approximation Theory","volume":"311 ","pages":"Article 106191"},"PeriodicalIF":0.9000,"publicationDate":"2025-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Approximation Theory","FirstCategoryId":"100","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0021904525000498","RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MATHEMATICS","Score":null,"Total":0}
引用次数: 0
Abstract
The study of interpolation nodes and their associated Lebesgue constants is a cornerstone of numerical analysis, directly influencing the stability and accuracy of polynomial approximations. In this paper, we examine the Morrow–Patterson points, a specific set of interpolation nodes introduced to construct cubature formulas with the minimal number of points in a square for a fixed degree . We prove that their Lebesgue constant has minimal rate of growth of at least .
期刊介绍:
The Journal of Approximation Theory is devoted to advances in pure and applied approximation theory and related areas. These areas include, among others:
• Classical approximation
• Abstract approximation
• Constructive approximation
• Degree of approximation
• Fourier expansions
• Interpolation of operators
• General orthogonal systems
• Interpolation and quadratures
• Multivariate approximation
• Orthogonal polynomials
• Padé approximation
• Rational approximation
• Spline functions of one and several variables
• Approximation by radial basis functions in Euclidean spaces, on spheres, and on more general manifolds
• Special functions with strong connections to classical harmonic analysis, orthogonal polynomial, and approximation theory (as opposed to combinatorics, number theory, representation theory, generating functions, formal theory, and so forth)
• Approximation theoretic aspects of real or complex function theory, function theory, difference or differential equations, function spaces, or harmonic analysis
• Wavelet Theory and its applications in signal and image processing, and in differential equations with special emphasis on connections between wavelet theory and elements of approximation theory (such as approximation orders, Besov and Sobolev spaces, and so forth)
• Gabor (Weyl-Heisenberg) expansions and sampling theory.