matrix := [
[7,0,0,0,0,0,0,0,0,0,0],
[0,0,7,0,0,0,0,0,0,0,0],
[6,6,6,0,0,0,0,0,0,0,0],
[0,0,0,0,7,0,0,0,0,0,0],
[0,0,0,0,0,0,7,0,0,0,0],
[0,0,0,0,0,0,0,7,0,0,0],
[0,0,0,7,0,0,0,0,0,0,0],
[0,0,0,6,0,0,0,0,7,0,0],
[0,0,0,0,7,7,0,0,0,0,0],
[0,0,0,0,0,0,0,0,0,0,7],
[4,0,0,3,7,4,7,4,4,6,6]
]*Z(13);