×

Quadratic decomposition of a Laguerre-Hahn polynomial sequence. II. (English) Zbl 1241.33011

Summary: In [Bull. Belg. Math. Soc. - Simon Stevin 17, No. 4, 641–659 (2010; Zbl 1225.42016)] the authors proved that a quasi-symmetric orthogonal polynomial sequence \(\{R_{n}\}_{n \geq 0}\) is a Laguerre-Hahn sequence if and only if the component \(\{P_{n}\}_{n \geq 0}\) in its quadratic decomposition is also a Laguerre-Hahn sequence. In this paper and under these conditions, we deduce the class s of the Laguerre-Hahn sequence \(\{R_{n}\}_{n \geq 0}\). More precisely, if \(s'\) is the class of \(\{P_{n}\}_{n \geq 0}\) then \(2s' \leq s \leq 2s' + 3\). On the other hand the polynomial coefficients of the Riccati equation satisfied by the Stieltjes function corresponding to \(\{R_{n}\}_{n \geq 0}\) are given in terms of those of \(\{P_{n}\}_{n \geq 0}\). As an application, we determine all non-symmetric quasi-symmetric Laguerre-Hahn sequences of class one.

MSC:

33C45 Orthogonal polynomials and functions of hypergeometric type (Jacobi, Laguerre, Hermite, Askey scheme, etc.)
42C05 Orthogonal functions and polynomials, general theory of nontrigonometric harmonic analysis

Citations:

Zbl 1225.42016
Full Text: DOI

References:

[1] Alaya J., Maroni P.: Symmetric Laguerre-Hahn forms of class s = 1. Integral Transforms Spec. Funct. 4, 301–320 (1996) · Zbl 0865.42021 · doi:10.1080/10652469608819117
[2] H. Bouakkaz, Les polynômes orthogonaux de Laguerre-Hahn de classe zéro. Thèse de Troisième Cycle. Université Pierre et Marie Curie, Paris, 1990.
[3] H. Bouakkaz and P. Maroni, Description des polynômes orthogonaux de Laguerre-Hahn de classe zéro, in Orthogonal Polynomials and Their Applications, C. Brezinski et al. Editors. Annals Comput. Appl. Math. 9. Baltzer, Basel (1991), 189–196. · Zbl 0859.33007
[4] B. Bouras and F. Marcellán, Quadratic decomposition of a Laguerre-Hahn polynomial sequence I. Bull. Belg. Math. Soc. Simon Stevin (2010). In press. · Zbl 1225.42016
[5] Chihara T.S.: An Introduction to Orthogonal Polynomials. Gordon and Breach, New York (1978) · Zbl 0389.33008
[6] J. Dini, Sur les formes linéaires et les polynômes orthogonaux de Laguerre-Hahn. Thèse de Troisième Cycle. Université Pierre et Marie Curie, Paris, 1988.
[7] Dini J., Maroni P.: Sur la multiplication d’une forme linéaire par une fraction rationnelle. Applications aux formes de Laguerre-Hahn. Ann. Polon. Math. 52, 175–185 (1990) · Zbl 0714.42013
[8] Marcellán F., Petronilho J.: Eigenproblem for tridiagonal 2-Toeplitz matrices and quadratic polynomial mappings. Linear Algebra Appl. 260, 169–208 (1997) · Zbl 0877.15010
[9] Marcellán F., Prianes E.: Orthogonal polynomials and Stieltjes functions: The Laguerre-Hahn case. Rend. Mat. Appl. (7) 16(1), 117–141 (1996) · Zbl 0868.42009
[10] Marcellán F., Prianes E.: Perturbations of Laguerre-Hahn linear functionals. J. Comput. Appl. Math. 105, 109–128 (1999) · Zbl 0946.42013 · doi:10.1016/S0377-0427(99)00025-4
[11] Maroni P.: Sur la décomposition quadratique d’une suite de polynômes orthogonaux. I. Riv. di Mat. Pura ed Appl. 6, 19–53 (1990) · Zbl 0715.33009
[12] P. Maroni, Une théorie algébrique des polynômes orthogonaux. Application aux polynômes orthogonaux semi-classiques, in Orthogonal Polynomials and Their Applications, C. Brezinski et al. Editors. Annals Comput. Appl. Math. 9. Baltzer, Basel (1991), 95–130. · Zbl 0944.33500
[13] M. Zaatra, Polynômes orthogonaux de Laguerre-Hahn, Mémoire de Master de Mathématiques, Faculté des Sciences de Gabès, Tunisie, 2007. In French.
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.