Coefficient inequality for transforms of bounded turning functions. (English) Zbl 1418.30010
Summary: The objective of this paper is to obtain sharp upper bound for the second Hankel functional associ1 ated with the \(k^{th}\)root transform \(\big[{f}(z^{k})\big]^{\frac{1}{k}}\) of normalized analytic function \(f({z})\) when it belongs to bounded turning functions, defined on the open unit disc in the complex plane, with the help of Toeplitz determinants.
MSC:
| 30C45 | Special classes of univalent and multivalent functions of one complex variable (starlike, convex, bounded rotation, etc.) |
| 30C50 | Coefficient problems for univalent and multivalent functions of one complex variable |
References:
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