Izvestiya of Saratov University.

Mathematics. Mechanics. Informatics

ISSN 1816-9791 (Print)
ISSN 2541-9005 (Online)

For citation:

Starovoitov A. P. Quadratic Hermite – Padé Approximants of Exponential Functions. Izvestiya of Saratov University. Mathematics. Mechanics. Informatics, 2014, vol. 14, iss. 4, pp. 387-395. DOI: 10.18500/1816-9791-2014-14-4-387-395, EDN: TAAMHV

This is an open access article distributed under the terms of Creative Commons Attribution 4.0 International License (CC-BY 4.0).
Published online: 
01.12.2014
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Russian
Heading: 
Mathematics
UDC: 
517.538.52+517.538.53
DOI: 
10.18500/1816-9791-2014-14-4-387-395
EDN: 
TAAMHV

Quadratic Hermite – Padé Approximants of Exponential Functions

Autors: 
Starovoitov Alexander Pavlovich, Francisk Skorina Gomel State University
Abstract: 

The paper deals with extremal properties of diagonal quadratic Hermite – Pad’e approximants of type I for exponential system  {eλjz}2j =0 with arbitrary real λ0, λ1, λ2. Proved theorems complement known results of P. Borwein, F. Wielonsky.

Key words: 
Hermite – Pad’e approximants of type I
quadratic Hermite – Pad’e approximants
asymptotic equality
saddle-point method
References: 
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Received: 
15.06.2014
Accepted: 
03.11.2014
Published: 
01.12.2014
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