RT Journal Article T1 Generalized Delta coherent pairs A1 Kwon, Kil H. A1 Lee, J. H. A1 Marcellán Español, Francisco José AB A pair of quasi-definite linear functionals ${u_0,u_1}$ is a generalized $Delta$-coherent pair if monic orthogonal polynomials $${P_n(x)}_{n=0} nfty$$ and $${R_n(x)}_{n=0} nfty$$ relative to $u_0$ and $u_1$, respectively, satisfy a relation $$ R_n(x) = frac{1}{n+1}Delta P_{n+1}(x)-frac{sigma_n}{n}Delta P_n(x)- frac{ au_{n-1}}{n-1}Delta P_{n-1}(x), ~~ ngeq 2,$$ where $sigma_n$ and $ au_n$ are arbitrary constants and $Delta p=p(x+1)-p(x)$ is the difference operator. AB We show that if ${u_0,u_1}$ is a generalized $Delta$-coherent pair, then $u_0$ and $u_1$ must be discrete-semiclassical linearfunctionals. We also find conditions under which either $u_0$ or $u_1$ is discrete-classical. PB Korean Mathematical Society SN 0304 - 9914 YR 2004 FD 2004 LK https://hdl.handle.net/10016/5970 UL https://hdl.handle.net/10016/5970 LA eng NO 18 pages, no figures.-- MSC2000 codes: 42C05, 33C45. NO MR#: MR2095548 (2005k:33007) NO Zbl#: Zbl 1058.42018 NO The first author (KHK) was partially supported by KOSEF(R01{1999{00001). The second author(JHL) was supported by BK Postdoctoral Program in SNU. Thework of the third author (FM) was supported by Dirección General de Enseñanza Superior (DGES) of Spain under grant BFM2000-0206-C04-01. DS e-Archivo RD 27 may. 2024