Convergence of a formal power series and Gelfond-Leont’ev derivatives

Author S. I. Fedynyak, M. M. Sheremeta

Ivan Franko National University of Lviv

Abstract Given a formal power series, we establish conditions on the formal power seriess under which the series represents a function analytic in the disk $\{z\colon |z|\leq R\}, R\in (0, +\infty].$ We also give a survey of well-know results for the case $R=+\infty$.
Keywords formal power series; formal power series
DOI
doi:10.30970/ms.35.2.149-154
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Pages 149-154
Volume 35
Issue 2
Year 2011
Journal Matematychni Studii
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