#668, October 18 - October 24, 2025: The Weekly 'Unsolvable' Sudoku Puzzle
by Richard Kröger, guest compiler
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WARNING: This is the Weekly 'Unsolvable' Sudoku, rated above 'Extreme'.
This is currently unsolvable by my solver, except perhaps with trial and error strategies.
Using the solver will not help you. (much).
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Discussion...
Post an idea here...
... by: BGH
5 Step Solution to # 668
Basics 27.2
4 @ H8 29.6 Cell pair, one digit will be in the solution.
8 @ C8 35.8 Cell pair, one digit will be in the solution if this is a solution path.
5 @ D8 49.4 Cell pair, one digit will be in the solution if this is a solution path.
8 @ B6 56.8 Cell pair, one digit will be in the solution if this is a solution path.
7 @ D7 Solution. Cell pair, one digit will be in the solution if this is a solution path.
I could not find a unit pair that led to a solution.
... by: Serban
# 668 G7=8 Basics to 22
1. Number 9 n=2 e=7 N=27 Nc=34 Ns=7 => H9=9 basics to 43
1a. X chain x=6 =>[J1,F2,D4,H5,C9] <>6 => D1=6 solve
2. H9=9 & B4=1 solve
3. H9=9 & J1=2 solve
4. H9=9 & D4=3 solve
5. H9=9 & B9=4 solve
6. H9=9 & G6=6 solve
7. H9=9 & D7=7 solve
8. H9=9 & E4=8 solve
9. H9=9 & E6=9 solve