Maestro n° 103 : Page 84 - Gr 81
r1c6 =3= r1c9 -3-5- r1c9 =5= r1c7 -5- r4c7 =5= r4c6 -5-3- r4c6 =3= r4c4 => r2c4 et r4c6 ≠ 3