Maestro n° 100 : Page 82 - Gr 79
L1C7 -7- L1C2 =7=3= L1C2 -3- L3C2 =3=9= L3C2 -9- L3C6 =9= L1C6 -9-5- L1C6 =5= L1C7 donc L1C7 ≠ 7