Maestro n° 100 : Page 78 - Gr 75
L2C2 =7=9= L2C2 -9- L8C2 =9= L8C7 -9- L5C7 =9= L5C9 -9-6- L5C9 =6= L6C9 -6- L6C1 =6=5= L6C1 -5- L4C1 =5=7= L4C1 donc L1C1 et L4C2 ≠ 7