Naked Triple
Three cells in a unit whose candidate sets together cover only three digits. Lock those digits in; prune them from the rest.
Advanced sudoku technique
What it is
A naked triple extends the naked-pair idea to three cells. The three cells don't all need the same three candidates — they just need to be subsets of the same three-digit set. The common shapes are {a,b,c}/{a,b,c}/{a,b,c}, {a,b,c}/{a,b}/{b,c}, and the slightly trickier {a,b}/{b,c}/{a,c}. Whatever permutation of the three digits ends up in those three cells, no other cell in the unit can hold any of them. Naked triples often unlock the next chain of singles.
Want the full theory?
The Naked Triple guide on Sudoku247Wiki walks through the logic step by step, with worked examples, diagrams and FAQs.
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