Problem: SchursLemma_10_3

	// n_balls = number of balls
	// n_boxes = number of boxes
	Data n_balls := 10; n_boxes := 3;
	
	// d_boxes = number of box where can be a ball
	Domains Dom d_boxes = [1..n_boxes];
	
	// putIn = array wich contains the box where a ball is put in
	Variables IntVar putIn[n_balls] :: d_boxes;
	
	
	Constraints
		// For any triplet of balls: i, j and k
		Forall(i in [1..n_balls]) {
			Forall(j in [1..n_balls]) {
				Forall(k in [1..n_balls]) {
					// If the sum of i+j = k, then k can't be in the same box as i or j
					If (i+j=k) Then {
						(putIn[i] <> putIn[j]) Or (putIn[i] <> putIn[k]); }
				}
			}
		}