authors
- FIDALGO PRIETO, ULISES
- LOPEZ LAGOMASINO, GUILLERMO
Nikishin systems are perfect. The case of unbounded and touching supports
Articles
Overview
published in
- JOURNAL OF APPROXIMATION THEORY Journal
publication date
- June 2011
start page
- 779
end page
- 811
issue
- 6
volume
- 163
Digital Object Identifier (DOI)
International Standard Serial Number (ISSN)
- 0021-9045
Electronic International Standard Serial Number (EISSN)
- 1096-0430
abstract
- K. Mahler introduced the concept of perfect systems in the theory of simultaneous Hermite&-Padé approximation of analytic functions. Recently, we proved that Nikishin systems, generated by measures with bounded support and non-intersecting consecutive supports contained on the real line, are perfect. Here, we prove that they are also perfect when the supports of the generating measures are unbounded or touch at one point. As an application, we give a version of the Stieltjes theorem in the context of simultaneous Hermite&-Padé approximation.