# Problem 453: Lattice Quadrilaterals
A simple quadrilateral is a polygon that has four distinct vertices, has
no straight angles and does not self-intersect. Let Q(m, n) be the
number of simple quadrilaterals whose vertices are lattice points with
coordinates (x,y) satisfying 0 ≤ x ≤ m and 0 ≤ y ≤ n. For example, Q(2,
2) = 94 as can be seen below: It can also be verified that Q(3, 7) =
39590, Q(12, 3) = 309000 and Q(123, 45) = 70542215894646. Find Q(12345,
6789) mod 135707531.