Surveys in Mathematics and its Applications

ISSN 1842-6298 (electronic), 1843-7265 (print)
Volume 9 (2014), 131 -- 138


T. V. Sudharsan and R. Vijaya

Abstract. In this paper, we obtain sharp upper bounds for the functional |a2a4 - a32| for functions belonging to S*(α, β) and C(α, β). Our results extend corresponding previously known results.

2010 Mathematics Subject Classification: Primary 30C80; Secondary 30C45.
Keywords: Coefficient bounds; Fekete-Szego functional; Hankel determinant.

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T. V. Sudharsan R. Vijaya
Department of Mathematics, Department of Mathematics,
SIVET College, S.D.N.B. Vaishnav College,
Chennai - 600 073, India. Chennai - 600 044, India.
E-mail: E-mail: