deletions | additions       diff --git a/Version3.tex b/Version3.tex  index 9e6ceca..57d0438 100644  --- a/Version3.tex  +++ b/Version3.tex 
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$$  $$  \sum_{i=0}^{n-1} f_2(n,i) = (c+d)\sum_{i=0}^{n-1} \sum_{j=i}^{n-1} (\sum_{j=i}^{n-1} 1) +   \frac{d}{2}n(n-1)\sum_{i=0}^{n-1}  1 +   \frac{d}{2}\sum_{i=0}^{n-1} i^2 +   \frac{d}{2}(1-2n)\sum_{i=0}^{n-1} i  $$