Abstract
For finite Blaschke products B of degree \(n \geqslant 2,\) \(B(0) = 0,\) \(B'(0) \ne 0\) a sharp upper bound for the least critical values and a sharp lower bound for the greatest critical values of these products are established. These estimates depend only on n and \(\left| {B'(0)} \right|\).
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Funding
This work was supported by the Russian Foundation for Basic Research (project no. 20-01-00018) and by the Ministry of Education and Science of the Russian Federation (additional agreement of April 21, 2020, no. 075-02-2020-1482-1).
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Translated by I. Ruzanova
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Dubinin, V.N. Critical Values of Finite Blaschke Products. Dokl. Math. 104, 163–164 (2021). https://doi.org/10.1134/S1064562421040050
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DOI: https://doi.org/10.1134/S1064562421040050