Coefficient estimates for bi-concave functions

Abstract

In this study,a new class C_{Σ}^{p,q}(α) of analytic and bi-concave functions were presented in the open unit disc. The coefficients estimates on the first two Taylor-Maclaurin coefficients |a₂| and |a₃| were found for functions belonging to this class.

Keywords

• Analytic,bi-concave functions,analytic function,univalent function,bi-univalent function,concave function

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