AbstractIn the early 1970s, Bro. U. Alfred Brousseau asked for the number of regions formed in an infinite strip by the mn segments that join m equally spaced points on one edge to n equally spaced points on the other. Using projective duality, we express the number of points, segments, and regions formed by Brousseau's configuration in terms of the numbers Lk(m,n) of lines that meet an m × n lattice array in exactly k points