Candidate skills
Naked Triples in Sudoku: The Next Step After Pairs
Three cells can reserve three digits even when each cell shows more than two candidates.
A naked triple is a reservation: three cells in one unit collectively contain only three digits. Those digits cannot appear elsewhere in the unit.
The cells do not need to show the same three candidates individually, which is why the pattern is easy to overlook.
Find the three-cell set
Look in one row, column or box for three cells whose combined candidates contain exactly three digits. Examples include 12, 13 and 23, or 123, 13 and 23.
Confirm the unit
All three cells must share the same row, column or box. A visually close group across different units is not a triple and cannot justify an elimination.
Remove only outside candidates
Delete those three digits from every other cell in the unit. Do not erase candidates inside the triple, even if one cell has a wider-looking list.
Recheck definitions
If the union contains four digits, or if a fourth cell also participates, the set is not a naked triple. Precise counting prevents an attractive but invalid pattern.
Follow the reveal
The elimination often exposes a single, pair or locked candidate. Return to the affected unit immediately and explain the new move before searching elsewhere.
A small checklist
- Find three cells with three combined digits
- Keep all cells in one unit
- Eliminate only outside the set
- Count the candidate union exactly
- Rescan after the elimination
Put it into practice
Open today’s calm challenge
Use one idea from this article on a verified puzzle. There is no need to finish quickly.
Play today’s Sudoku