Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics

We consider the following discrete Sobolev inner product involving the Gegenbauer weight $$(f,g)_S:=\int_{-1}^1f(x)g(x)(1-x^2)^{\alpha}dx+M\big[f^{(j)}(-1)g^{(j)}(-1)+f^{(j)}(1)g^{(j)}(1)\big],$$ where $\alpha>-1,$ $j\in \mathbb{N}\cup \{0\},$ and $M>0.$ Our main objective is to calculat...

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Egile Nagusiak: Littlejohn, Lance L., Mañas Mañas, Juan Francisco, Moreno Balcázar, Juan José, Wellman, Richard
Formatua: info:eu-repo/semantics/article
Hizkuntza:English
Argitaratua: 2024
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Sarrera elektronikoa:http://hdl.handle.net/10835/15245
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author Littlejohn, Lance L.
Mañas Mañas, Juan Francisco
Moreno Balcázar, Juan José
Wellman, Richard
author_facet Littlejohn, Lance L.
Mañas Mañas, Juan Francisco
Moreno Balcázar, Juan José
Wellman, Richard
author_sort Littlejohn, Lance L.
collection DSpace
description We consider the following discrete Sobolev inner product involving the Gegenbauer weight $$(f,g)_S:=\int_{-1}^1f(x)g(x)(1-x^2)^{\alpha}dx+M\big[f^{(j)}(-1)g^{(j)}(-1)+f^{(j)}(1)g^{(j)}(1)\big],$$ where $\alpha>-1,$ $j\in \mathbb{N}\cup \{0\},$ and $M>0.$ Our main objective is to calculate the exact value $$r_0 = \lim_{n\rightarrow \infty}\frac{\log \left(\max_{x\in [-1,1]} |\widetilde{Q}_n^{(\alpha,M,j)}(x)|\right)}{\log \widetilde{\lambda}_n}, \quad \alpha\ge -1/2,$$ where $\{\widetilde{Q}_n^{(\alpha,M,j)}\}_{n\geq0}$ is the sequence of orthonormal polynomials with respect to this Sobolev inner product. These polynomials are eigenfunctions of a differential operator and the obtaining of the asymptotic behavior of the corresponding eigenvalues, $\widetilde{\lambda}_n$ , is the principal key to get the result. This value $r_0$ is related to the convergence of a series in a left--definite space. In addition, to complete the asymptotic study of this family of nonstandard polynomials we give the Mehler--Heine formulae for the corresponding orthogonal polynomials.
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spelling oai:repositorio.ual.es:10835-152452024-01-18T08:16:37Z Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics Littlejohn, Lance L. Mañas Mañas, Juan Francisco Moreno Balcázar, Juan José Wellman, Richard Sobolev orthogonality differential operators asymptotics We consider the following discrete Sobolev inner product involving the Gegenbauer weight $$(f,g)_S:=\int_{-1}^1f(x)g(x)(1-x^2)^{\alpha}dx+M\big[f^{(j)}(-1)g^{(j)}(-1)+f^{(j)}(1)g^{(j)}(1)\big],$$ where $\alpha>-1,$ $j\in \mathbb{N}\cup \{0\},$ and $M>0.$ Our main objective is to calculate the exact value $$r_0 = \lim_{n\rightarrow \infty}\frac{\log \left(\max_{x\in [-1,1]} |\widetilde{Q}_n^{(\alpha,M,j)}(x)|\right)}{\log \widetilde{\lambda}_n}, \quad \alpha\ge -1/2,$$ where $\{\widetilde{Q}_n^{(\alpha,M,j)}\}_{n\geq0}$ is the sequence of orthonormal polynomials with respect to this Sobolev inner product. These polynomials are eigenfunctions of a differential operator and the obtaining of the asymptotic behavior of the corresponding eigenvalues, $\widetilde{\lambda}_n$ , is the principal key to get the result. This value $r_0$ is related to the convergence of a series in a left--definite space. In addition, to complete the asymptotic study of this family of nonstandard polynomials we give the Mehler--Heine formulae for the corresponding orthogonal polynomials. 2024-01-18T08:16:36Z 2024-01-18T08:16:36Z 2018-06 info:eu-repo/semantics/article Lance L . Littlejohn, Juan F. Mañas Mañas, Juan J. Moreno Balcázar and Richard Wellman. Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics, J. Approx. Theory. 230 (2018), 32--49. 0021-9045 http://hdl.handle.net/10835/15245 en https://doi.org/10.1016/j.jat.2018.04.008 Grant MTM2014-53963-P and grant P11-FQM-7276 Attribution-NonCommercial-NoDerivatives 4.0 Internacional http://creativecommons.org/licenses/by-nc-nd/4.0/ info:eu-repo/semantics/openAccess Lance L . Littlejohn, Juan F. Mañas Mañas, Juan J. Moreno Balcázar and Richard Wellman. Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics, J. Approx. Theory. 230 (2018), 32--49.
spellingShingle Sobolev orthogonality
differential operators
asymptotics
Littlejohn, Lance L.
Mañas Mañas, Juan Francisco
Moreno Balcázar, Juan José
Wellman, Richard
Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics
title Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics
title_full Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics
title_fullStr Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics
title_full_unstemmed Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics
title_short Differential operator for discrete Gegenbauer--Sobolev orthogonal polynomials: eigenvalues and asymptotics
title_sort differential operator for discrete gegenbauer--sobolev orthogonal polynomials: eigenvalues and asymptotics
topic Sobolev orthogonality
differential operators
asymptotics
url http://hdl.handle.net/10835/15245
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AT manasmanasjuanfrancisco differentialoperatorfordiscretegegenbauersobolevorthogonalpolynomialseigenvaluesandasymptotics
AT morenobalcazarjuanjose differentialoperatorfordiscretegegenbauersobolevorthogonalpolynomialseigenvaluesandasymptotics
AT wellmanrichard differentialoperatorfordiscretegegenbauersobolevorthogonalpolynomialseigenvaluesandasymptotics