Practise: Empty Rectangle
Start in the marked box: the 6-notes form an L-shape with one deliberately empty corner. Two short links outside the box complete the deduction.
The prepared notes show the box pattern and two matching outside links. Find the empty corner first; this is a candidate removal, not a placement.
Example 1 of 4
Your turn first
Your turn first
For 6, find the L-shape in the marked box. Which outer candidate sees both ends of the linked row and column?
Remember
An Empty Rectangle leaves one box corner free of a digit. With two matching row and column links, at least one outer end must hold that digit; a candidate seeing both outer ends can be removed.
Put it to use
Where you will meet it
Expert grids are the only place this pattern regularly decides the solve. Bring your notes.
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