On the Van Vleck theorem for limit-periodic continued fractions of general form

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Abstract

The boundary properties of functions representable as limit-periodic continued fractions of the form A 1(z)/(B 1(z) + A 2(z)/(B 2(z) +...)) are studied; here the sequence of polynomials {A n } n=1 has periodic limits with zeros lying on a finite set E, and the sequence of polynomials {B n } n=1 has periodic limits with zeros lying outside E. It is shown that the transfinite diameter of the boundary of the convergence domain of such a continued fraction in the external field associated with the fraction coincides with the upper limit of the averaged generalized Hankel determinants of the function defined by the fraction. As a consequence of this result combined with the generalized Pólya theorem, it is shown that the functions defined by the continued fractions under consideration do not have a single-valued meromorphic continuation to any neighborhood of any nonisolated point of the boundary of the convergence set.

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Copyright information

© Pleiades Publishing, Ltd. 2017

Authors and Affiliations

  1. 1.Steklov Mathematical Institute of Russian Academy of SciencesMoscowRussia

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