Removing apparent singularities of linear difference systems. (January 2021)

• Record Type: Journal Article
• Authors: Barkatou, Moulay A.; Jaroschek, Maximilian
• Is Part Of: Journal of symbolic computation. Volume 102(2020)
• Page Start: 86
• Page End: 107
• Publication Date: 2021-01
• Subjects: Systems of linear difference equations -- Apparent singularities -- Desingularization -- Removable singularities; Mathematics -- Data processing -- Periodicals; Numerical analysis -- Data processing -- Periodicals; Automatic programming (Computer science) -- Periodicals; Mathématiques -- Informatique -- Périodiques; Analyse numérique -- Informatique -- Périodiques; Programmation automatique -- Périodiques; Automatic programming (Computer science); Mathematics -- Data processing; Numerical analysis -- Data processing; Periodicals; Electronic journals; 510.285
• DOI: 10.1016/j.jsc.2019.10.010
• Languages: English
• ISSNs: 0747-7171

Abstract

Abstract: It is well known that for a first order system of linear difference equations with rational function coefficients, a solution that is holomorphic in some left half plane can be analytically continued to a meromorphic solution in the whole complex plane. The poles stem from the singularities of the rational function coefficients of the system. Just as for systems of differential equations, not all of these singularities necessarily lead to poles in a solution, as they might be what is called removable. In our work, we show how to detect and remove these singularities and further study the connection between poles of solutions, removable singularities and the extension of numerical sequences at these points.