TADM2E 2.35
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Revision as of 17:56, 14 October 2016 by Letientai299 (talk | contribs) (Correct the function again. The implementation in previous edit has 2 mistakes: `n` and `2*i` are excluded. The problem states that `for i=1 to n do`, which should mean `n` is included. Same for `2*i`)
1. Summations:
for i=1 to n do for j=i to 2*i do output foobar
$ \begin{align} &T(n)=\sum_{i=1}^{n}\sum_{j=i}^{2*i}1\\ \end{align} $
2. Simplification:
$ \begin{align} &T(n)=\sum_{i=1}^{n}\sum_{j=i}^{2*i}1=\sum_{i=1}^{n}(2i-i+1)= \sum_{i=1}^{n}(i+1)=\frac{n(n+1)}{2}+n \end{align} $