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arXiv · 2609.16676

When can a power series be analytically continued?

Kei Beauduin
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Abstract

A classical line of research characterizes analytic continuation of power series through analytic interpolation of their coefficients. Under suitable hypotheses, the growth of the interpolating function reflects the geometry of the continuation domain, and conversely. We survey the development of these results from Leau and Le Roy through Lindelöf, Carlson, Dufresnoy$\unicode{x2013}$Pisot and Arakelian. We formulate the main results in a unified notation using compactifications of the complex plane. In particular, we give a comprehensive treatment of Carlson's second continuation theorem, which has received little attention, and prove a refinement based on the Laplace transform.

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Kei Beauduin. 2026-09-15. When can a power series be analytically continued?. https://arxiv.org/abs/2609.16676

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