Naked Pairs
Naked Pairs: when two cells in the same row, column or box hold exactly the same two candidates, those two digits are locked into that pair and can be removed from the rest of the unit.
Use when two cells in the same unit share the exact same two candidates.
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Two cells in the row are limited to the same pair, {3,8}.
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Those digits are locked between them, so 3 and 8 leave every other cell of the row.
Imagine a sudoku where in a specific row, only cells A2 and A8 can contain numbers 3 and 7. If we solve that A2 must contain 3, we automatically know that A8 must contain 7.
- Treating cells as a pair when one of them has a third candidate — both must hold exactly the same two.
- Forgetting that the elimination only applies inside the unit the pair shares.
Frequently asked questions
What is a naked pair?
Two cells in a unit limited to the same two candidates. They lock those digits between them, clearing the pair from the rest of the unit.