Row 0 is the first row, it will have a 1. Row 1 is actually the second row it will have 1 and 1, but not to be confused with 11. The next row is the numbers 1 and 2 and 1. Now how did we get these numbers? 1 is ALWAYS going to be the first number in the row, but in order to make the triangle grow you add the two numbers above. Example: 1 + 2 = 3 and 2 + 1 = 3, so for the next line we will have 1 (always on the outside) and 3 and 3 and then 1 again. The next line gets even bigger, 1 (outside again) 1 + 3 = 4, and 3 + 3 = 6, and 3 + 1 = 4, and then that 1 again.
This can go on as long as anyone wants it to go.