Difference between revisions of "Talk:Algo-analysis-TADM2E"

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-Hello, I have a solution to the task 2-34 (TADM2E 2.34) but I have no permissions to created/edit anything.
-Here is the solution:
-This task refers to this song The_Twelve_Days_of_Christmas_(song)
-So we have to calculate the sum like this
-day - 1 gift
-day - 1 gift + 2 gifts
-day - 1 + 2 + 3
-n day - 1 + 2 + 3 + ... + n
-Formula is
-<math>
-\begin{align}
-&\sum_{i=1}^n \sum_{j=1}^n j\
-= \sum_{i=1}^n \frac{n(n+1)}{2} =\\
-&= \frac{1}{2}\sum_{i=1}^n n^2 + \frac{1}{2}\sum_{i=1}^n n=\\
-&= \frac{n(n+1)(2n+1) + 3n(n+1)}{12} = \frac{(n+1)(n^2+2n)}{6}\
-\end{align}
- </math>

Latest revision as of 07:07, 27 May 2020