sum of the terms of an arithmetic sequence
- Let (`u_(n)`) be an arithmetic sequence of common difference 3, and of first term `u_(0)= -3`. Let S be the sum of `u_(3)` to `u_(30)`. S=`u_(3)`+`u_(4)`+`u_(5)`+`. . .`+`u_(30)`.
- Compute the number of terms in S.
- Compute S.
Course reminder : Numerical sequences