Math Insight

The hardest Sudoku puzzles require techniques equivalent to propositional logic — the same foundation used in computer proofs.

Math Insight

The hardest Sudoku puzzles require techniques equivalent to propositional logic — the same foundation used in computer proofs.

PlaySudoku.us
Medium · Puzzle #284
✓ Completed! 👍
1
9
7
3
4
8
4
5
9
1
5
2
4
1
9
9
4
1
5
8
6
1
8
4
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6
9
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1
7
8
00:00
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Pro Tip

If pointing pairs aren't visible, try box-line reduction. They're inverses — if one fails, try the other.

Pro Tip

If pointing pairs aren't visible, try box-line reduction. They're inverses — if one fails, try the other.