deletions | additions       diff --git a/p4.tex b/p4.tex  index e426e57..b85d223 100644  --- a/p4.tex  +++ b/p4.tex 
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$2^{901} = 2 mod 7$  {\bf$2^{902} $2^{902}  = 4 mod 7$} 7$  \end{itemize}