matrix := [
[0,0,7,0,0,0,0],
[0,0,0,7,0,0,0],
[6,8,1,5,0,0,0],
[6,1,7,6,0,0,0],
[0,0,0,0,0,0,7],
[6,0,9,3,4,7,12],
[7,4,5,1,6,0,6]
]*Z(13);