Windowed Sudoku
Outside numbers total the three nearest cells.
Also known as Outside Sum Sudoku.
How to play Windowed Sudoku
- Standard 9×9 sudoku: 1–9 exactly once per row, column and 3×3 box.
- Each number outside the grid is the sum of the three cells nearest it in that row or column.
- All four sides are marked, so every row and every column carries a sum at each end.
Where to start
A 6 outside a row can only be 1, 2 and 3 in some order in the three cells nearest it.
Difficulty
Puzzles are generated on your device, so there is an endless supply of them. Windowed Sudoku comes in 2 grades — or work up the endless track, where every level is generated a little harder than the last.