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On some properties of Hermite–Padé approximants to an exponential system

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Abstract

Extremal properties and localization of zeros of general (including nondiagonal) type I Hermite–Padé polynomials are studied for the exponential system {e λjz} k j=0 with arbitrary different complex numbers λ0, λ1,..., λk. The theorems proved in the paper complement and generalize the results obtained earlier by other authors.

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  1. Francisk Skorina Gomel State University, Savetskaya vul. 104, Gomel, 246019, Belarus

    A. P. Starovoitov & E. P. Kechko

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Original Russian Text © A.P. Starovoitov, E.P. Kechko, 2017, published in Trudy Matematicheskogo Instituta imeni V.A. Steklova, 2017, Vol. 298, pp. 338–355.

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Starovoitov, A.P., Kechko, E.P. On some properties of Hermite–Padé approximants to an exponential system. Proc. Steklov Inst. Math. 298, 317–333 (2017). https://doi.org/10.1134/S0081543817060190

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