For any grid, x by x, figure out a formula for the greatest number of points that can be put on the inside of the grid such that no three points are colinear.

(In reply to re: Theoretical limits reachable? by Justin)

You can't put an X in the middle of the 7x7 because colinear does not limit lines to horizontal, vertical and major diagonals.  There are many other diagonals which would be affected by an X in the middle.

Posted by Erik O. on 2005-05-19 19:12:49