Discriminants and functional equations for polynomials orthogonal on the unit circle

Citation
Meh. Ismail et Ns. Witte, Discriminants and functional equations for polynomials orthogonal on the unit circle, J APPROX TH, 110(2), 2001, pp. 200-228
Citations number
36
Categorie Soggetti
Mathematics
Journal title
JOURNAL OF APPROXIMATION THEORY
ISSN journal
00219045 → ACNP
Volume
110
Issue
2
Year of publication
2001
Pages
200 - 228
Database
ISI
SICI code
0021-9045(200106)110:2<200:DAFEFP>2.0.ZU;2-6
Abstract
We derive raising and lowering operators fbr orthogonal polynomials on the unit circle and find second order differential and q-difference equations f or these polynomials. A general functional equation is found which allows o ne to relate the zeros of the orthogonal polynomials to the stationary valu es of an explicit quasi-energy and implies recurrences on the orthogonal po lynomial coefficients. We also evaluate the discriminants and quantized dis criminants of polynomials orthogonal on the unit circle. (C) 2001 Academic Press.