\setlength{\oddsidemargin}{0.0in}
\setlength{\evensidemargin}{0.0in}
\setlength{\topmargin}{0.0in}
\setlength{\topskip}{0.5in}
\setlength{\headheight}{0.5in}
\setlength{\headsep}{0in}
\setlength{\textwidth}{6.5in}
\setlength{\textheight}{8.0in}
\setlength{\parindent}{0in}
\setlength{\parskip}{0.1in}

\setcounter{secnumdepth}{4}
\setcounter{tocdepth}{4}

% \usepackage{times}
\usepackage{fancyvrb}
\usepackage{relsize}
\usepackage{hyperref}
\usepackage{graphicx}
\usepackage{color}
\usepackage{listings}

% theorems, etc.
\usepackage{amsmath}
\newtheorem{theorem}{Theorem}
\newcommand{\BlackBox}{\rule{1.5ex}{1.5ex}}  % end of proof
\newenvironment{proof}{\par\noindent{\bf Proof\ }}{\hfill\BlackBox\\[2mm]}
\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{proposition}[theorem]{Proposition}
\newtheorem{remark}[theorem]{Remark}
\newtheorem{corollary}[theorem]{Corollary}
\newtheorem{definition}[theorem]{Definition}
\newtheorem{conjecture}[theorem]{Conjecture}
\newtheorem{axiom}[theorem]{Axiom}

% for problem sets, each problem automatically numbered
\newcounter{problemnum}
\newcommand{\oneproblem}
   { \stepcounter{problemnum} {\bf \arabic{problemnum}}. } 
\newcommand{\startproblemset}
   { \bigskip {\bf\large Exercises} \setcounter{problemnum}{0} }