English

Bloch and Landau constants for meromorphic functions

Complex Variables 2026-03-06 v1

Abstract

Let M1(λ)\mathcal{M}_1(\lambda) be the class of all meromorphic functions ff in the unit disk D={zC}:z<1\mathbb{D}=\{z\in\mathbb{C}\}: |z|<1 having a simple pole at λD{0}\lambda \in \overline{\mathbb{D}} \setminus \{0\} and satisfying the normalization f(0)=1f'(0)=1. Let B(λ)B(\lambda) and L(λ)L(\lambda) denote the Bloch and Landau constants, respectively, for this class. In this article, we first show that the Bloch constant B(1)B(1) and the Landau constant L(1)L(1) are infinite. Using these results and a conformal mapping technique, we establish that B(p)B(p) and L(p)L(p) are likewise infinite for any p(0,1)p \in (0,1), thereby refuting a recent conjecture. Finally, we extend our study to the class of meromorphic functions having two simple poles and prove that their associated Bloch and Landau constants also remain infinite.

Cite

@article{arxiv.2603.05047,
  title  = {Bloch and Landau constants for meromorphic functions},
  author = {Md Firoz Ali and Shaesta Azim},
  journal= {arXiv preprint arXiv:2603.05047},
  year   = {2026}
}
R2 v1 2026-07-01T11:04:42.820Z