Bull. Korean Math. Soc. 2006; 43(1): 179-188
Printed March 1, 2006
Copyright © The Korean Mathematical Society.
Rosihan M. Ali, M. Hussain~Khan, V. Ravichandran, and K. G.Subramanian
Universiti Sains Malay-sia, Islamiah College, Universiti Sains Mal-aysia, Madras Christian College
For a given $p$-valent analytic function $g$ with positive
coefficients in the open unit disk $\UD$, we study a class of
functions $f(z)=z^p-\sum_{n=m}^\infty a_nz^n$\ ($a_n\geq 0$) satisfying
\[ \frac{1}{p}\Re \left( \frac{z(f*g)'(z)}{(f*g)(z)}\right)
> \alpha\quad (0\leq \alpha<1; z\in\Delta).\]
Coefficient inequalities, distortion and covering theorems, as
well as closure theorems are determined. The results obtained
extend several known results as special cases.
Keywords: starlike function, convolution, subordination, negative coefficients
MSC numbers: 30C45
2002; 39(1): 122-131
2011; 48(4): 697-704
2023; 60(6): 1477-1496
2023; 60(2): 281-291
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