Bi-Concave Functions Connected with the Combination of the Binomial Series and the Confluent Hypergeometric Function

Abstract

In this article, we first define and then propose to systematically study some new subclasses of the class of analytic and bi-concave functions in the open unit disk. For this purpose, we make use of a combination of the binomial series and the confluent hypergeometric function. Among some other properties and results, we derive the estimates on the initial Taylor-Maclaurin coefficients |a2| and |a3| for functions in these analytic and bi-concave function classes, which are introduced in this paper. We also derive a number of corollaries and consequences of our main results in this paper.

Keywords

• analytic functions
• hadamard product (or convolution)
• univalent and bi-univalent functions
• Taylor-Maclaurin coefficients
• bi-concave functions
• pocchammer symbol