help!!!

The pattern is as follows:

2, 6, 12, 20.

For each tower, we can see we have the X² + X   - where X is the tower number.

So, let's say it was the 3rd tower.

So, substituting for the equation, we get:

3² + 3 = 12

If we check, that is true. The 3rd tower does have 12 blocks. 

Let's find the total for the 99th tower.

Total = 99² + 99 = 9900

Therefore, the 99th tower has 9900 blocks. 

(Solved by a 12 y/o) 

Those towers honestly looks like my hand pointing up.