2,282 research outputs found

    A note on a class of pp-valent starlike functions of order beta

    Full text link
    In this paper we obtain sharp coefficient bounds for certain pp-valent starlike functions of order β\beta, 0≤β<10\le \beta<1. Initially this problem was handled by Aouf in "M. K. Aouf, On a class of pp-valent starlike functions of order α\alpha, Internat. J. Math. &\& Math. Sci. 1987;10:733--744". We pointed out that the proof given by Aouf was incorrect and a correct proof is presented in this paper.Comment: 6 pages, 1 table, submitted to a journa

    Bounds for the Second Hankel Determinant of Certain Univalent Functions

    Full text link
    The estimates for the second Hankel determinant a_2a_4-a_3^2 of analytic function f(z)=z+a_2 z^2+a_3 z^3+...b for which either zf'(z)/f(z) or 1+zf"(z)/f'(z) is subordinate to certain analytic function are investigated. The estimates for the Hankel determinant for two other classes are also obtained. In particular, the estimates for the Hankel determinant of strongly starlike, parabolic starlike, lemniscate starlike functions are obtained
    • …
    corecore