Find the sum to `n` terms of the series: `3+9+15+35+63+`

Explanation

To find the sum to \( n \) terms of the series \( 3 + 9 + 15 + 35 + 63 + \ldots \), we will first identify the general term of the series and then derive the sum.

### Step 1: Identify the General Term
We observe the given terms:
- \( 3 = 2^2 - 1 \)
- \( 9 = 4^2 - 7 \)
- \( 15 = 6^2 - 21 \)
- \( 35 = 8^2 - 29 \)
...