Ladder operators and a second--order difference equation for general discrete Sobolev orthogonal polynomials

Autor: Filipuk, Galina, Mañas-Mañas, Juan F., Moreno-Balcázar, Juan J.
Rok vydání: 2020
Předmět:
Zdroj: Journal of Difference Equations and Applications (2022)
Druh dokumentu: Working Paper
DOI: 10.1080/10236198.2022.2103412
Popis: We consider a general discrete Sobolev inner product involving the Hahn difference operator, so this includes the well--known difference operators $\mathscr{D}_{q}$ and $\Delta$ and, as a limit case, the derivative operator. The objective is twofold. On the one hand, we construct the ladder operators for the corresponding nonstandard orthogonal polynomials and we obtain the second--order difference equation satisfied by these polynomials. On the other hand, we generalise some related results appeared in the literature as we are working in a more general framework. Moreover, we will show that all the functions involved in these constructions can be computed explicitly.
Comment: Preprint of the version published in Journal of Difference Equations and Applications with the title "Second--order difference equation for Sobolev--type orthogonal polynomials: Part I: theoretical results"
Databáze: arXiv