Annular itineraries for entire functions

Abstract

In order to analyse the way in which the size of the iterates $(f^n(z))$ of a transcendental entire function $f$ can behave, we introduce the concept of the {\it annular itinerary} of a point $z$. This is the sequence of non-negative integers $s_0{s}_1...$ defined by \[ f^n(z)\in A_{s_n}(R),\;\;\text{for}n\ge 0, \] where $A_0(R)=\{z:|z|<R\}$ and \[ A_n(R)=\{z:M^{n-1}(R)\le |z|<M^n(R)\},\;\;n\ge 1. \] Here $M(r)$ is the maximum modulus of $f$ and $R>0$ is so large that $M(r)>r$, for $r\ge R$. We consider the different types of annular itineraries that can occur for any transcendental entire function $f$ and show that it is always possible to find points with various types of prescribed annular itineraries. The proofs use two new annuli covering results that are of wider interest.

References in corpus (1)

• Fast escaping points of entire functions