• Title of article

    On partial sums of certain meromophic -valent functions

  • Author/Authors

    Aouf، نويسنده , , M.K. and Mostafa، نويسنده , , A.O.، نويسنده ,

  • Issue Information
    روزنامه با شماره پیاپی سال 2009
  • Pages
    7
  • From page
    1325
  • To page
    1331
  • Abstract
    In this paper, we study the ratio of meromorphic p -valent functions in the punctured disk U ∗ = { z : 0 < | z | < 1 } of the form f ( z ) = 1 z p + ∑ k = 1 ∞ a k + p − 1 z k + p − 1 to its sequence of partial sums of the form f ( z ) = 1 z p + ∑ k = 1 n + p − 1 a k + p − 1 z k + p − 1 . Also, we determine sharp lower bounds for Re { f ( z ) / f n + p − 1 ( z ) } , Re { f n + p − 1 ( z ) / f ( z ) } , Re { f ′ ( z ) / f n + p − 1 ′ ( z ) } and Re { f n + p − 1 ′ ( z ) / f ′ ( z ) } .
  • Keywords
    Partial sums , Meromorphic p -valent functions
  • Journal title
    Mathematical and Computer Modelling
  • Serial Year
    2009
  • Journal title
    Mathematical and Computer Modelling
  • Record number

    1596654