Techniques › Naked Triple
Naked Triple
Three cells sharing three candidates between them lock those digits away.
Three cells in a house whose candidates, taken together, come to exactly three digits. They need not each hold all three — {2,5}, {5,8} and {2,8} is a perfectly good Naked Triple, and is the shape most people miss.
The three cells take the three digits between them in some order, so no other cell in the house can hold any of them.
A worked example
Taken from a real puzzle in our bank, at the point where this was the cheapest move available. Pattern candidates are marked in amber; anything the step eliminates is struck through in red.
| 8 | 5 | 1 | 37 | 27 | 347 | 24 | 9 | 6 |
| 9 | 4 | 2 | 1 | 8 | 6 | 7 | 5 | 3 |
| 3 | 7 | 6 | 59 | 29 | 459 | 8 | 1 | 24 |
| 2 | 8 | 5 | 6 | 79 | 79 | 3 | 4 | 1 |
| 7 | 9 | 4 | 2 | 3 | 1 | 6 | 8 | 5 |
| 1 | 6 | 3 | 4 | 5 | 8 | 9 | 2 | 7 |
| 5 | 3 | 7 | 89 | 1 | 29 | 24 | 6 | 248 |
| 6 | 2 | 8 | 35 | 4 | 35 | 1 | 7 | 9 |
| 4 | 1 | 9 | 78 | 6 | 27 | 5 | 3 | 28 |
- NudgeA few cells in column 6 share the same small set of candidates between them.
- WhereNaked Triple in column 6: r4c6, r7c6, r9c6
- Do itRemove r1c6 ≠ 7, r3c6 ≠ 9
How to spot it
Look for three cells in a house with two or three candidates each, and check whether their union is exactly three digits. The partial shapes are the ones worth training your eye on.
Where you will meet it
Naked Triple sits at tier 2 of our ladder, which means it first becomes necessary at Medium. Puzzles below that band never require it, though it may still appear as a shortcut.
Read next
- Naked Pair Two cells in a house holding the same two candidates lock those digits away from the rest.
- Naked Quad Four cells sharing four candidates between them. Rare, and usually preempted.
- Hidden Triple Three digits restricted to the same three cells clear everything else out of them.