Sue de Coq

Sue de Coq uses cells at the intersection of a box and line, combined with companion sets in the line and box. When candidates partition correctly, multiple eliminations become possible.

Technique

1. Find 2-3 cells at a box-line intersection containing N+2 candidates (forming an AALS).
2. Find a companion set in the same line outside the box.
3. Find another companion set in the same box outside the line.
4. If candidates partition between intersection and companions, eliminate from other cells.

Tips

• Sue de Coq is elegant but rare.
• The intersection cells must share candidates with both companions.
• Eliminations can occur in both the line and the box outside the pattern.