matrix := [ [0,7,0,0,0,0,0,0,0], [7,0,0,0,0,0,0,0,0], [0,0,0,7,0,0,0,0,0], [0,0,7,0,0,0,0,0,0], [0,0,0,0,0,7,0,0,0], [0,0,0,0,7,0,0,0,0], [0,0,0,0,0,0,0,0,7], [2,11,7,6,6,7,11,7,2], [0,0,0,0,0,0,7,0,0] ]*Z(13);