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Expert · Puzzle #520
1
6
8
7
3
9
4
4
3
8
9
2
1
8
6
4
9
5
6
3
4
1
7
6
"As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality." — Albert Einstein
"As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality." — Albert Einstein
Always update pencil marks immediately after placing a digit — stale marks cause almost all solving errors.
Always update pencil marks immediately after placing a digit — stale marks cause almost all solving errors.