20 CHIFFRES EN 12 GRILLES DE 5 NUMEROS G=5/9
Tableau du système:
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | |
| N° | . | . | . | . | . | . | . | . | . | . | . | . | . | . | . | . | . | . | . | . |
| 1 | . | . | . | . | . | X | X | X | X | X | X | X | X | X | X | X | X | X | X | X |
| 2 | . | X | X | X | X | . | . | . | . | X | X | X | X | X | X | X | X | X | X | X |
| 3 | . | X | X | X | X | X | X | X | X | . | . | . | . | X | X | X | X | X | X | X |
| 4 | . | X | X | X | X | X | X | X | X | X | X | X | X | . | . | . | . | X | X | X |
| 5 | X | . | X | X | X | . | X | X | X | . | X | X | X | . | X | X | X | . | X | X |
| 6 | X | . | X | X | X | X | . | X | X | X | . | X | X | X | . | X | X | X | . | X |
| 7 | X | . | X | X | X | X | X | . | X | X | X | . | X | X | X | . | X | X | X | . |
| 8 | X | X | . | X | X | . | X | X | X | X | . | X | X | X | X | X | . | X | X | . |
| 9 | X | X | . | X | X | X | . | X | X | X | X | X | . | X | X | . | X | . | X | X |
| 10 | X | X | . | X | X | X | X | X | . | X | X | . | X | . | X | X | X | X | . | X |
| 11 | X | X | X | . | X | X | X | . | X | . | X | X | X | X | X | X | . | X | . | X |
| 12 | X | X | X | . | X | X | X | X | . | X | X | X | . | X | . | X | X | X | X | . |