Circles-and-Squares Fractal

$\begin{figure}\begin{center}\BoxedEPSF{Circles_and_Squares.epsf}\end{center}\end{figure}$

A Fractal produced by iteration of the equation

$\begin{displaymath} z_{n+1}={z_n}^2\ ({\rm mod\ } m) \end{displaymath}$

which results in a Møiré-like pattern.