2020/06/14 by Allu, Vasudevarao, Pandey, Abhishek · 1 citation
#30C45 #30C50 #Complex Variables (math.CV) #FOS: Mathematics
paper · doi:10.48550/arxiv.2006.07783
Let A denote the class of analytic functions in the unit disk \mathbbD of the form f(z)= z+∑n=2∞an zn and S denote the class of functions f\inA which are univalent (\it i.e., one-to-one). In 1960s, L. Zalcman conjectured that |an2-a2n-1|≤ (n-1)2 for n≥ 2, which implies the famous Bieberbach conjecture |an|≤ n for n≥ 2. For f∈ S, Ma \citeMa-1999 proposed a generalized Zalcman conjecture |anam-an+m-1|≤ (n-1)(m-1) for n≥ 2, m≥ 2. Let U be the class of functions f\inA satisfying |f'(z)((z)/(f(z)))2-1 |lt; 1 for z∈\mathbbD. and F denote the class of functions f∈ A satisfying \rm Re (1-z)2f'(z)>0 in \mathbbD. In the present paper, we prove the Zalcman conjecture and generalized Zalcman conjecture for the class U using extreme point theory. We also prove the Zalcman conjecture and generalized Zalcman conjecture for the class F for the initial coefficients.