deletions | additions       diff --git a/p7.tex b/p7.tex  index 235ce57..0f2406a 100644  --- a/p7.tex  +++ b/p7.tex 
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\item  Let n=5:  $4! \equiv -1\(\textrm{mod}\n)$ -1\ (\textrm{mod}\n)$  \end{itemize}