[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.4134/BKMS.2014.51.5.1551

COEFFICIENT DISCS AND GENERALIZED CENTRAL FUNCTIONS FOR THE CLASS OF CONCAVE SCHLICHT FUNCTIONS

Bhowmik, Bappaditya (Bappaditya Bhowmik Department of Mathematics Indian Institute of Technology Kharagpur)
Wirths, Karl-Joachim (Institut fur Analysis and Algebra TU Braunschweig)

Publication Information

Bulletin of the Korean Mathematical Society / v.51, no.5, 2014 , pp. 1551-1559 More about this Journal

Abstract

We consider functions that map the open unit disc conformally onto the complement of an unbounded convex set with opening angle ${\pi}{\alpha}$ , ${\alpha}{\in}(1,2]$ , at infinity. We derive the exact interval for the variability of the real Taylor coefficients of these functions and we prove that the corresponding complex Taylor coefficients of such functions are contained in certain discs lying in the right half plane. In addition, we also determine generalized central functions for the aforesaid class of functions.

Keywords

concave function with bounded opening angle at infinity; coefficient region; generalized central functions;

Citations & Related Records

Reference

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