*Problem #7*

Given the *m*×*n* array of points whose first coordinates
come from the set {1,2,...,m} and whose second coordinates come from the
set {1,2,...,n}, what is the total number of lines determined by all
pairs of these points? For example when *m* = 3 and *n* = 2,
the figure below shows that there are 11 lines (3 vertical, 2
horizontal, 4 at a 45 degree angle, and 2 other diagonals).
**
The solution will be posted shortly.
**

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