BrianO wrote:I could be wrong here... but I think its 18.
would it be 3 x 3 x 2 x 1 = 18
(I haven't done this kind of maths in a long time!!!)
If the numbers x, y and z are smudged, the possible pin options are:
x, x, y, z ----------------------------------- y, y, z, x -------------------------- z, z, x, y
x, x, z, y ----------------------------------- y, y, x, z -------------------------- z, z, y, x
x, y, x, z ----------------------------------- y, z, y, x -------------------------- z, x, z, y
x, y, z, x ----------------------------------- y, z, x, y -------------------------- z, x, y, z
x, z, x, y ----------------------------------- y, x, y, z -------------------------- z, y, z, x
x, z, y, x ----------------------------------- y, x, z, y -------------------------- z, y, x, z
y, x, x, z ----------------------------------- z, y, y, x -------------------------- x, z, z, y
y, x, z, x ----------------------------------- z, y, x, y -------------------------- x, z, y, z
y, z, x, x ----------------------------------- z, x, y, y -------------------------- x, y, z, z
z, x, x, y ----------------------------------- x, y, y, z -------------------------- y, z, z, x
z, x, y, x ----------------------------------- x, y, z, y -------------------------- y, z, x, z
z, y, x, x ----------------------------------- x, z, y, y -------------------------- y, x, z, z
36 in total .... I don't think there are any errors - each of the above possible possiblities contains x, y and z with one of them duplicated once.