\hoffset=-.25  truein \voffset=-0.5 truein \oddsidemargin=0.0 truein
\topmargin=-.15 truein \textwidth=7.0 truein \textheight=8.91 truein

%some convenient definitions.

\newenvironment{keeptogether}{\pagebreak[0]\samepage}{}

\newenvironment{In}[1]{\setlength{\parskip}{3ex}
\noindent {\sl In[#1]:=} \begin{mm} \nopagebreak}{\end{mm}}

\newenvironment{Out}[1]{\setlength{\parskip}{3ex} \samepage
\noindent {\sl Out[#1]=}\, \begin{math} \begin{mm}
\displaystyle}%
{\end{mm} \end{math} \vspace{3ex}}
\newcommand{\InB}[1]{{\sl In[#1]\/}}
\newcommand{\OutB}[1]{{\sl Out[#1]\/}}
\newcommand{\m}{\tt}
\newenvironment{mm}{\m}{}

\def\cl{\centerline} 
\def\mma{{\it Mathematica\/}} 
\def\eg{{\it e.g.\/}} 
\def\etc{{\it etc.\/}} 
\def\ie{{\it i.e.\/}}
\def\ni{\noindent}
\def\out[#1]{{\ni \sl Out[#1]=}}