On the convergence of multidimensional S-fractions with independent variables

Autor: O.S. Bodnar, R.I. Dmytryshyn, S.V. Sharyn
Jazyk: English<br />Ukrainian
Rok vydání: 2020
Předmět:
Zdroj: Karpatsʹkì Matematičnì Publìkacìï, Vol 12, Iss 2, Pp 353-359 (2020)
Druh dokumentu: article
ISSN: 2075-9827
2313-0210
DOI: 10.15330/cmp.12.2.353-359
Popis: The paper investigates the convergence problem of a special class of branched continued fractions, i.e. the multidimensional S-fractions with independent variables, consisting of \[\sum_{i_1=1}^N\frac{c_{i(1)}z_{i_1}}{1}{\atop+}\sum_{i_2=1}^{i_1}\frac{c_{i(2)}z_{i_2}}{1}{\atop+} \sum_{i_3=1}^{i_2}\frac{c_{i(3)}z_{i_3}}{1}{\atop+}\cdots,\] which are multidimensional generalizations of S-fractions (Stieltjes fractions). These branched continued fractions are used, in particular, for approximation of the analytic functions of several variables given by multiple power series. For multidimensional S-fractions with independent variables we have established a convergence criterion in the domain \[H=\left\{{\bf{z}}=(z_1,z_2,\ldots,z_N)\in\mathbb{C}^N:\;|\arg(z_k+1)|
Databáze: Directory of Open Access Journals