Strong Asymptotics of Hermite-PadéApproximants for Angelesco Systems

Yattselev, Maxim L.

Canadian journal of mathematics, Tome 68 (2016) no. 5, pp. 1159-1200

Résumé

In this work type II Hermite-Padé approximants for a vector of Cauchy transforms of smooth Jacobi-type densities are considered. It is assumed that densities are supported on mutually disjoint intervals (an Angelesco system with complex weights). The formulae of strong asymptotics are derived for any ray sequence of multi-indices.

Détail

DOI : 10.4153/CJM-2015-043-3

Mots-clés : 42C05, 41A20, 41A21, Hermite-Padé approximation, multiple orthogonal polynomials, non-Hermitian orthogonality, strong asymptotics, matrix Riemann-Hilbert approach

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