In case someone don't know what a pattern lock is, they are like this:
I am curious on the probability of randomly cracking one of these 'passwords', given that the length of the grid is
3x3 and that we know the pattern length (e.g number of lines).
Also, you may or not noticed but the pattern can go in both
Note: we can have multiple lines that go to a single dot, but we can never draw a line above another line (I think some apps allow this, but for this question lets assume we will not).