sum of the terms of an arithmetic sequence
- Let (`u_(n)`) be an arithmetic sequence of common difference -6, and of first term `u_(0)= 1`. Let S be the sum of `u_(2)` to `u_(9)`. S=`u_(2)`+`u_(3)`+`u_(4)`+`. . .`+`u_(9)`.
- Compute the number of terms in S.
- Compute S.
Course reminder : Numerical sequences