grandmaitre n° 17 : Page 51 - Grille 38
L4C1 =7=1= L4C1 -1- L4C4 =1= L9C4 -1-9- L9C4 =9= L7C6 -9- L1C6 =9=6= L1C6 -6- L3C5 =6= L3C7 -6- L9C7 =6=7= L9C7 -7- L9C5 =7=1= L9C5 -1- L5C5 =1= L5C1 donc L4C1 ≠ 1 et L5C1 ≠ 7