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