PlaySudoku.us
Expert · Puzzle #133
1
7
8
6
7
4
3
2
9
8
7
3
4
1
9
9
6
2
5
1
2
4
1
5
8
Techniques used
- Naked Single
- Hidden Single
- Naked Pair
- Pointing Pair
- Skyscraper
- 2-String Kite
- XY-Wing
- UR Type 1
- Swordfish
Set theory provides the formal foundation for Sudoku's rules: each digit must appear exactly once per set.
Set theory provides the formal foundation for Sudoku's rules: each digit must appear exactly once per set.
"The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it." — Bertrand Russell
"The point of philosophy is to start with something so simple as not to seem worth stating, and to end with something so paradoxical that no one will believe it." — Bertrand Russell