The increment of row number in a formula has to do with the functions that are utilized in the successfulness of increment.
But first, we need data like this:
Increasing row numbers
Proof that there is a success in the increment by clicking on the small square that shows on lower-right corner of the dark green, and drag it to left.
Note: It is better to stick to 3 because after the third it will show the same number over and over again.
In conclusion, after following those two steps, you should have something like this.