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How to Videos Forum Rankings Books Print   Solution 6 Aug 2026
Easy:
4×4
5×5
Sudoku
Medium:
4×4
5×5
6×6
8×8
Killer
Sudoku
Difficult:
4×4
5×5
6×6
8×8
12×12
Extra
Difficult 8 × 8, Rating: ★★★★★      Solved 210 times
abcdefgh
1 
3 :
2 mod
 
8
20+
 
 
56×
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2 
 
1 mod
 
10+
 
 
1 mod
 
3 
8
0 mod
7
1 mod
8+
13+
 
2
4 
2 mod
 
7+
 
 
 
1 mod
20×
5 
 
56×
 
0-
 
 
 
 
6 
1 mod
 
4 mod
 
6
2 mod
4-
 
7 
 
5
 
17+
3
 
 
8 
15+
 
 
 
 
1 mod
 
 

Note: this puzzle also uses the modulo operator mod
a mod b = r means that when dividing a by b, the remainder is r. For example, 5 mod 2 = 1, and 3 mod 5 = 3.
Look here for a longer explanation.

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