deletions | additions       diff --git a/4b2.tex b/4b2.tex  index 9204892..c5ca055 100644  --- a/4b2.tex  +++ b/4b2.tex 
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& (i + 1 \leq n + 1) \a (res * i = i!) &\\  \iff & \T &  \end{split}  \end{equation} This holds true since $i \leq n \iff i + 1 \leq n + 1$