Let's focus on every other number.
We have: 36, 90, 144, ... 9437184.
The common difference is 54, so let's set every to a multiple of 54.
54, 108, 162, ... 9437202.
Dividing these terms by 54, we get:
1,2,3,...174763.
Remember, we are counting every other number, so there are really:
174763 * 2 = 349526 terms in the sequence.
