The New Sudoku Players' Forum

[swaatacba]

I'm looking to solve last Saturday's (28/04/2017) Sudoku puzzle from the UK's Guardian newspaper. I can make progress if I indulge in using progressive "Naked Tuples", but this progression involves swapping dimensions. I'd like to confirm that the dimension swap is valid and logical.

Here is a picture of the puzzle. The red ovals match 1,6 Tuples from the central sub grid and allows the elimination of 6 from the available contenders 4,6,9 in cell (5,6). This leaves a new naked tuple of 4,9 in cells (5,6) and (6,6) - marked in orange. This allows the elimination of these values from cell (9,6), giving cell result of 6. Does this make sense?

SuDoku_GUA20170429_FullDataGrid.PNG

[JasonLion]

Your eliminations are valid, but depending on what you mean by "dimension swap", the logic may or may not be exactly what you think it is.

The Naked Pair of 1 and 6 in R4C4 and R4C5 is a naked pair in both row 4 and in box 5. Thus it causes eliminations in both contexts. It isn't that you have found a naked pair in on dimension and can make eliminations in another dimension. It is more like you found a naked pair that can be viewed in two different ways, and you get to use both interpretations to make eliminations.

In a similar way, the subsequent naked pair of 4 and 9 in R5C6 and R6C6 can be viewed as happening in block 5 and in column 6. The column 6 view has an elimination in this case.

[swaatacba]

Thank you, Jason.