deletions | additions       diff --git a/header.tex b/header.tex  index ef2ffd0..a797456 100644  --- a/header.tex  +++ b/header.tex 
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\usepackage{amssymb}  \usepackage{amsthm}  \usepackage{stmaryrd}  \usepackage[normalem]{ulem}  \newtheorem{definition}{Definition}  \newtheorem{lemma}{Lemma}