3. Tap Puzzles. 4. Tap Sudoku. 5. Tap a puzzle. 6. Tap the square with a checkmark in the top right corner of the screen. 7. Tap Autocheck. Now if you place a number in the wrong spot, your iPhone ...

the answer is an astonishingly large number: As mentioned above, there are over 6 sextillion possible Sudoku grids. And also as with many questions in combinatorics, the process of getting that ...