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\setlength{\textwidth}{6.5 in}
\setlength{\textheight}{8.5 in}
\setlength{\headsep}{0.75 in}
\setlength{\parindent}{0 in}
\setlength{\parskip}{0.1 in}
\usepackage{amsmath,amsthm,amssymb}
\usepackage{graphicx}
\usepackage{amssymb}
\usepackage{amsmath,esint}
\usepackage{amssymb,xcolor,trimclip}
\usepackage{algorithm}
\usepackage{algorithmic}
\usepackage{amsmath,amsfonts,graphicx}

\newcounter{sessionnum}
\renewcommand{\thepage}{\thesessionnum-\arabic{page}}
\renewcommand{\thesection}{\thesessionnum.\arabic{section}}
\renewcommand{\theequation}{\thesessionnum.\arabic{equation}}
\renewcommand{\thefigure}{\thesessionnum.\arabic{figure}}
\renewcommand{\thetable}{\thesessionnum.\arabic{table}}

%
% The following macro is used to generate the header.
%
\newcommand{\lecture}[3]{
   \pagestyle{myheadings}
   \thispagestyle{plain}
   \newpage
   \setcounter{sessionnum}{#1}
   \setcounter{page}{1}
   \noindent
   \begin{center}
   \framebox{
      \vbox{\vspace{2mm}
    \hbox to 6.28in { {\bf CS320: Value of Data \& AI
		\hfill Winter 2020} }
       \vspace{4mm}
       \hbox to 6.28in { {\Large \hfill Session #1   \hfill} }
       \vspace{2mm}
       \hbox to 6.28in { {\it Lecturer(s): #2 \hfill Scribes: #3} }
      \vspace{2mm}}
   }
   \end{center}
   \markboth{Lecture #1: #2}{Lecture #1: #2}

   {\bf Disclaimer}: {\it These notes have not been subjected to the
   usual scrutiny reserved for formal publications.  They may be distributed
   outside this class only with the permission of the Instructor.}
   \vspace*{4mm}
}

\renewcommand{\cite}[1]{[#1]}
\def\beginrefs{\begin{list}%
        {[\arabic{equation}]}{\usecounter{equation}
         \setlength{\leftmargin}{2.0truecm}\setlength{\labelsep}{0.4truecm}%
         \setlength{\labelwidth}{1.6truecm}}}
\def\endrefs{\end{list}}
\def\bibentry#1{\item[\hbox{[#1]}]}


\newcommand{\fig}[3]{
			\vspace{#2}
			\begin{center}
			Figure \thesessionnum.#1:~#3
			\end{center}
	}
% Use these for theorems, lemmas, proofs, etc.
\newtheorem{theorem}{Theorem}[sessionnum]
\newtheorem{lemma}[theorem]{Lemma}
\newtheorem{proposition}[theorem]{Proposition}
\newtheorem{definition}[theorem]{Definition}
\newenvironment{proof}{{\bf Proof:}}{\hfill\rule{2mm}{2mm}}


\begin{document}
\lecture{1}{Lecturar names}{scribe-name}

\section{Stuff}
Blah blah
\end{document}






