For branched continued fractions of a special form (branched continued fractions with independent variables for fixed values of the variables), the notion of \(\mathcal{C}\)-figure convergence is introduced and used to establish a two-dimensional generalization of the Thron–Jones theorem on the parabolic domains of convergence of continued fractions. We propose a new method for the investigation of parabolic domains of convergence of branched continued fractions of a special form. This method does not use the Stieltjes–Vitali theorem on convergence of sequences of holomorphic functions. Hence, it enables us to extend the parabolic domain of convergence to a form similar to that obtained for the one-dimensional case. In proving the theorem, we essentially use the property of stability of continued fractions under perturbations established in the present work.
Similar content being viewed by others
References
T. M. Antonova, “Multidimensional generalization of the theorem on parabolic domains of convergence of continued fractions,” Mat. Met. Fiz.-Mekh. Polya, 42, No. 4, 7–12 (1999).
O. E. Baran, “Some domains of convergence of branched continued fractions of a special form,” Karpat. Mat. Publ., 5, No. 1, 4–13 (2013).
D. I. Bodnar, Branched Continued Fractions [in Russian], Naukova Dumka, Kiev (1986).
D. I. Bondar and R. I. Dmytryshyn, “Multidimensional associated fractions with independent variables and multiple power series,” Ukr. Mat. Zh., 71, No. 3, 325–339 (2019); English translation: Ukr. Math. J., 71, No. 3, 370–386 (2019).
D. I. Bondar and Kh. I. Kuchmins’ka, “Parabolic domain of convergence for two-dimensional continued fractions,” Mat. Stud., 4, 29–36 (1995).
R. I. Dmytryshyn, “On the expansion of some functions in a two-dimensional g-fraction with independent variables,” Mat. Met. Fiz.-Mekh. Polya, 53, No 4, 28–34 (2010); English translation: J. Math. Sci., 181, No. 3, 320–327 (2012).
TX. M. Antonova and R. I. Dmytryshyn, “Truncation error bounds for the branched continued fraction ,” Ukr. Mat. Zh., 72, No. 7, 877–885 (2020); English translation: Ukr. Math. J., 72, No. 7, 1018–1029 (2020).
T. Antonova, R. Dmytryshyn, and V. Kravtsiv, “Branched continued fraction expansions of Horn’s hypergeometric function H3 ratios,” Mathematics, 9 (2021).
I. Bilanyk and D. Bodnar, “Convergence criterion for branched continued fractions of the special form with positive elements,” Carpath. Math. Publ., 9, No. 1, 13–21 (2017).
I. Bilanyk, D. Bodnar, and L. Buyak, “Representation of a quotient of solutions of a four-term linear recurrence relation in the form of a branched continued fraction,” Carpath. Math. Publ., 11, No. 1, 33–41 (2019).
D. I. Bodnar and I. B. Bilanyk, “Parabolic convergence regions of branched continued fractions of the special form,” Carpath. Math. Publ., 13, No. 3, 619–630 (2021).
R. I. Dmytryshyn, “Convergence of some branched continued fractions with independent variables,” Mat. Stud., 47, No. 2, 150–159 (2017).
R. I. Dmytryshyn, “Multidimensional regular C-fraction with independent variables corresponding to formal multiple power series,” Proc. Roy. Soc. Edinburgh, Sec. A, 1–18 (2019); https://doi.org/10.1017/prm.2019.2.
R. I. Dmytryshyn, “On some of convergence domains of multidimensional S-fractions with independent variables,” Carpath. Math. Publ., 11, No. 1, 54–58 (2019).
R. I. Dmytryshyn and S. V. Sharyn, “Approximation of functions of several variables by multidimensional S-fractions with independent variables,” Carpath. Math. Publ., 13, No. 3, 592–607 (2019).
W. B. Gragg and D. D.Warner, “Two constructive results in continued fractions,” SIAM J. Numer. Anal., 20, No. 3, 1187–1197 (1983).
W. B. Jones andW. J. Thron, Continued Fractions: Analytic Theory and Applications, Addison-Wesley Publ. Comp., Reading (1980).
W. B. Jones and W. J. Thron, “Convergence of continued fractions,” Canad. J. Math., 20, 1037–1055 (1968).
W. J. Thron, “Two families of twin convergence regions for continued fractions,” Duke Math. J., 10, No. 4, 677–685 (1943).
H. S. Wall, Analytic Theory of Continued Fractions, D. Van Nostrand, New York (1948).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 74, No. 9, pp. 1155–1169, September, 2022. Ukrainian DOI: https://doi.org/10.37863/umzh.v74i9.7096.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Bilanyk, I.B., Bodnar, D.I. Two-Dimensional Generalization of the Thron–Jones Theorem on the Parabolic Domains of Convergence of Continued Fractions. Ukr Math J 74, 1317–1333 (2023). https://doi.org/10.1007/s11253-023-02138-1
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11253-023-02138-1