\documentclass{article}
%  Author:  Brian S. Marks
%  Title:  scr.tex
%  This latex file should be paired with the Matlab script scr.m, which 
%  creates the included yl.tex file.  The Matlab script creates a set of 
%  TikZ lines that create the figure of a circle circumscribed by a 
%  regular triangle, circumscribed by a circle, circumscribed by a 
%  square, etc.  

\usepackage{tikz}


\begin{document}

\begin{center}
	\input{yl.tikz}
\end{center}

The radius of the innermost circle is 1.  It is circumscribed by an 
equilateral triangle, which is circumscribed by a circle, and so forth.  
The radius of the circle as the number of figures approaches $\infty$ is 
\[
  \prod_{n=3}^\infty \sec\left(\frac{\pi}{n}\right) \approx 8.7
\]


\end{document}
