N represents any number that you may plug into it so, N could be 1, 100, -25, any integer.
lets make a pattern starting at 1 and ending at 5
(1) x 3 +1= 4 (2) x 3 +1=7 (3) x 3 +1=10 (4) x 3 +1=13 (5) x 3 +1=16
As you can see, whatever integer you plug into n it will either go up by 3 or go down by three if you use negatives. So your pattern is +-3 and that goes for whatever integer you plug into N.
