On Some Properties of Hermite--Pad\'e Approximants to an Exponential System

A. P. Starovoitov ; E. P. Kechko

Informatics and Automation, Complex analysis and its applications, Tome 298 (2017), pp. 338-355.

Résumé

Extremal properties and localization of zeros of general (including nondiagonal) type I Hermite–Padé polynomials are studied for the exponential system $\{e^{\lambda _jz}\}_{j=0}^k$ with arbitrary different complex numbers $\lambda _0,\lambda _1,\dots ,\lambda _k$. The theorems proved in the paper complement and generalize the results obtained earlier by other authors.

Détail

Keywords: exponential system, asymptotic equalities
Mots-clés : Hermite–Padé approximants, zeros of a polynomial.

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