Maestro n° 097 : Page 74 - Gr 71
L7C3 =1= L4C3 -1-6- L4C3 =6= L4C7 -6- L6C9 =6= L3C9 -6-5- L3C9 =5= L3C8 -5-1- L3C8 =1= L9C8 donc L7C7 et L9C2 ≠ 1