Improved Bohr inequalities for certain class of harmonic univalent functions

被引:9
作者
Ahamed, Molla Basir [1 ]
Allu, Vasudevarao [1 ]
Halder, Himadri [1 ]
机构
[1] Indian Inst Technol Bhubaneswar, Sch Basic Sci, Bhubaneswar, India
关键词
Analytic; univalent; harmonic functions; starlike; convex; close-to-convex functions; coefficient estimate; growth theorem; Bohr radius; POWER-SERIES; THEOREM; BASES;
D O I
10.1080/17476933.2021.1988583
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
Let H be the class of complex-valued harmonic mappings f = h + (g) over bar defined in the unit disk D := {z is an element of C : vertical bar z vertical bar < 1}, where h and g are analytic functions in D with the normalization h(0) = 0 = h'(0) - 1 and g(0) = 0. Let H-0 = {f = h + <(g)over bar> is an element of H: g'(0) = 0}. Let P-H(0)(M) := {f = h+ (g) over bar is an element of H-0 : Re (zh '' (Z))( > -M + vertical bar Zg ''(z)vertical bar, z is an element of D and M > 0}.) be the class of harmonic univalent mappings in the unit disk D, [Ghosh N, Allu V. On some subclasses of harmonic mappings. Bull Aust Math Soc. 2020;101:130-140.]. In this paper, we obtain the sharp Bohr-Rogosinski inequality, improved Bohr inequality, refined Bohr inequality and Bohr-type inequality for the class P-H(0)(M).
引用
收藏
页码:267 / 290
页数:24
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