The ‘Pointing Triples’ technique is similar to ‘Pointing Pairs’ but comes into play when a candidate number is repeated in three cells within the same row or column of a particular 3×3 block. This occurrence indicates that the number must be in one of these three cells, allowing you to eliminate this candidate number from other cells in the adjacent blocks within the same row or column.
To illustrate the ‘Pointing Triples’ technique, let’s consider an example. As shown in the first image, write all notes to mark potential numbers in a 3×3 block and its shared row. In the target block, the number six appears three times in the same row, and it also appears once in the row outside the block highlighted with the green frame. According to Sudoku rules, the number six must be present at least once in the left block. Therefore, you can safely remove the six from other cells in the row outside the block, as shown in the second image.
Using the same logic applied to rows, ‘Pointing Triples’ also applies to columns that share a 3×3 block with them. This method allows you to reduce your notes by cutting out unnecessary possibilities for some numbers. Download our free printable Sudoku puzzle books and have more fun.