Delgado, Antonia M.Marcellán Español, Francisco José2009-12-042009-12-042005-06Journal of Computational and Applied Mathematics, 2005, vol. 178, n. 1-2, p. 155-1680377-0427https://hdl.handle.net/10016/595114 pages, no figures.-- MSC2000 codes: Primary 33C45; 42C05.-- Issue title: "Proceedings of the Seventh International Symposium on Orthogonal Polynomials,Special Functions and Applications" (University of Copenhagen, Denmark, Aug 18-22, 2003).MR#: MR2127877 (2006f:33006)Zbl#: Zbl 1077.42016Given two symmetric and positive definite linear functionals, W and V, we study the coefficients in the recurrence relation for the system of monic polynomials orthogonal with respect to the second linear functional assuming that the first one is classical and that there exists an algebraic–differential relation between these two families of polynomials. Moreover, we determine this companion linear functional as a rational modification of the classical one.application/pdfeng© ElsevierOrthogonal polynomialsLinear functionalsSymmetric linear functionalsSobolev inner productresearch articleMatemáticas10.1016/j.cam.2004.02.026open access