Radius Constants for Functions with the Prescribed Coefficient Bounds

oleh: Om P. Ahuja, Sumit Nagpal, V. Ravichandran

Format: Article
Diterbitkan: Hindawi Limited 2014-01-01

Deskripsi

For an analytic univalent function f(z)=z+∑n=2∞anzn in the unit disk, it is well-known that an≤n for n≥2. But the inequality an≤n does not imply the univalence of f. This motivated several authors to determine various radii constants associated with the analytic functions having prescribed coefficient bounds. In this paper, a survey of the related work is presented for analytic and harmonic mappings. In addition, we establish a coefficient inequality for sense-preserving harmonic functions to compute the bounds for the radius of univalence, radius of full starlikeness/convexity of order α  (0≤α<1) for functions with prescribed coefficient bound on the analytic part.