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Hard · Puzzle #545
6
1
9
2
9
6
7
3
8
1
7
5
6
2
4
4
3
8
2
6
1
3
2
4
5
4
9
6
"Taking it altogether I find it is the most beautiful and important discovery of Nature that ever has been made since the world's creation." — Newton, about calculus
"Taking it altogether I find it is the most beautiful and important discovery of Nature that ever has been made since the world's creation." — Newton, about calculus
Competitive Sudoku solvers can hold the full pencil-mark state of a 9×9 grid in working memory, updating it mentally as they go.
Competitive Sudoku solvers can hold the full pencil-mark state of a 9×9 grid in working memory, updating it mentally as they go.