Asymptotic Behavior of Fractional Derivatives of Bounded Analytic Functions
I. Chyzhykov and Yu. Kosaniak
Faculty of Mechanics and Mathematics, Lviv Ivan Franko National University
1 Universytetska Str., Lviv 79000, Ukraine
E-mail: firstname.lastname@example.org yulia email@example.com
Received December 20, 2015, revised October 29, 2016
We find sharp sufficient conditions for the boundedness of fractional
derivatives of a bounded analytic function in a Stolz angle. If
F ≠ 0 in
the unit disc, the necessary and sufficient conditions for the boundedness of fractional derivatives of its argument in a Stolz angle are established.
Mathematics Subject Classification 2000: 30D50. Key words: bounded analytic function, Stolz angle, Blaschke product, fractional derivative.
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