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Tens of thousands of hardest Sudoku puzzles waiting for you to solve.

As proven by mathmaticians, The fewest clues possible for a proper Sudoku is 17.
And here is a collection of 49,151 unique 17-clue puzzles waiting for you!

- You can choose to play a random puzzle, or a certain one. All puzzles are numbered, from #1 to #49151.
- You can finish a puzzle solely with mouse or solely with keyboard (even number pad), with customizable shortcut keys.
- Smart UI designs to minimize your work.

Enjoy!