Shohat–Favard type theorem for orthogonal series

Autor: Jeannette Van Iseghem
Rok vydání: 2008
Předmět:
Zdroj: Journal of Computational and Applied Mathematics. 219(2):537-550
ISSN: 0377-0427
DOI: 10.1016/j.cam.2007.05.020
Popis: A function f is considered in the form of its formal series expansion @?"k"="0^~f"kP"k where (P"k)"k"="0^~ denotes a given system of orthogonal polynomials with respect to a measure on the real line. We prove that the denominators, numerators and residuals of their Frobenius-Pade approximation satisfy a five-term recurrence relation. The converse result is obtained: starting from the sequence of denominators, the function f is reconstructed, i.e. the analogous of the classical Shohat-Favard theorem is done.
Databáze: OpenAIRE