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The Guardian - UK
The Guardian - UK
Science
Alex Bellos

Did you solve it? Clueless Sudoku, a genius new puzzle

1995, CLUELESS
1995, CLUELESS
Photograph: Paramount Pictures/Allstar

Earlier today I set you these three Sudokus. They obey the standard rule of having all digits form 1 to 9 in each row, column and 3x3 box, with the extra rule:

A cell that contains its position in either its row, column or 3x3 box (read left-to-right, top-to-bottom) is coloured gold.

In other words, if a cell is gold, then it must describe its position in one of the three ways mentioned, and if a cell is white, it must not display its position. (For a more detailed explanation and a tutorial, see the original post.)

The extra constraint means there are no number clues in the starting grid, which is very elegant and makes for an entertaining solve.

Here they are again with solutions. If you want a pdf printout of all three puzzles, click here.

1. (This is a 6x6, so the numbers are from 1 to 6, and the boxes 2x3)

2.

3.

1.

2.

3.

Thanks to Alf Smith, who devised these puzzles.

I’ll be back in two weeks.

I’ve been setting a puzzle here on alternate Mondays since 2015. I’m always on the look-out for great puzzles. If you would like to suggest one, email me.

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