\documentclass[30pt,landscape]{foils}
\usepackage[pdftex]{geometry}
\geometry{headsep=3ex,hscale=0.9}
\usepackage[pdftex]{color} % for the colored block
\usepackage{pause}
\rightfooter{} % no more page numbers bottom right
\MyLogo{} % no logo bottom left
\begin{document}
\foilhead{An incrementally built formula page}
\[
   Q(n) = \sum_{i=1}^{n}i^{2} =
         \frac{1}{3}n(n+\frac{1}{2})(n+1)\pause
\]
\begin{eqnarray*}
\left|\frac{1}{3}n^3+\frac{1}{2}n^{2}+\frac{1}{6}n\right|
 &\leq&\left|\frac{1}{3}n^3\right|+\left|\frac{1}{2}n^{2}\right|
         +\left|\frac{1}{6}n\right|\pause\\
 &\leq&\frac{1}{3}|n^{3}|+\frac{1}{2}|n^{3}|+\frac{1}{6}|n^{3}|\\
 &=&|n^{3}|
\end{eqnarray*}
\end{document}