Korean Journal of Mathematics

The Kangwon-Kyungki Mathematical Society (강원경기수학회)
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BOUNDS OF HANKEL DETERMINANTS FOR ANALYTIC FUNCTION

  • Received : 2020.02.27
  • Accepted : 2020.11.05
  • Published : 2020.12.30
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Abstract

In this paper, we give estimates of the Hankel determinant H2(1) in a novel class 𝓝 (𝜀) of analytical functions in the unit disc. In addition, the relation between the Fekete-Szegö function H2(1) and the module of the angular derivative of the analytical function p(z) at a boundary point b of the unit disk will be given. In this association, the coefficients in the Hankel determinant b2, b3 and b4 will be taken into consideration. Moreover, in a class of analytic functions on the unit disc, assuming the existence of angular limit on the boundary point, the estimations below of the modulus of angular derivative have been obtained.

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References

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