(University of Eloued جامعة الوادي, 2019-04-23) Faghmous, Chadia; Bouras, Mohamed Cherif; Ali Khelil, Karima
In this work we present a new interpretation of Darboux
transforms in the context of 2-orthogonal polynomials and nd condi-
tions in order for any Darboux transform to yield a new set of 2- orthog-
onal polynomials. We also introduce the LU and UL factorizations of the
monic Jacobi matrix associated with a quasi-de nite linear functional
de ned on the linear space of polynomials with real coe¢ cients.