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#654, July 12 - July 18, 2025:
The Weekly 'Unsolvable' Sudoku Puzzle

by Andrew Stuart
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).

Archive

Each week a new 'unsolvable' will be published and the previous will be accessible here from this archive section. If you like very tough puzzles, these are for you.
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Tuesday 15-Jul-2025

... by: Envy E

Previous comment should read +7 G8 J8 in final line

With 7 eliminated from G9 then

+1 H9 (+7 G8 J8 ) +5 H2 (+7 H3 +7 B1) +4,6 A2 C2 +2 C1 +7 A9 +2 H9 -1 H9

G9 set to 1 in original puzzle leaves trivial solution

Tuesday 15-Jul-2025

... by: Envy E

After Solver runs out of known solutions

+2 J6 +4,7,9 J3,7,8 +7 G4

+2 J7 +9 H7 +9 A8 +3 B8 +7 G7 J7

G9 not 7

Monday 14-Jul-2025

... by: Frans Goosens

#654

C4=4 Wrong, Undo calculation
C4=9 ( H2=1 ) Solved,

Total solving time is : 34 sec.
Number of logical steps is : 1205

Sunday 13-Jul-2025

... by: BGH

1 Step Solution for #654 (after basics)
1 @ H2 (15 pair @ H2, one digit in solution)(Also Column 2 Unit 1's, one in the solution)
... (and column 2 has a quad)

Saturday 12-Jul-2025

... by: Dieter

#654 - initially populated cells: 25 = 30,9%
No solver used.
basics: F4=5, J2=8
populated cells = 27 = 33,3%
Numbers 5,8,1,2,3,6,7 occur most frequently.
combinations of C6 = (5,8,9) and D6 = (1,2,3,9)
1 matrix remains after basic checks: C6/D6 = 5/1
C6/D6 = 5/1 & A7=2 solves.

Review:
A7=2 solves.

Saturday 12-Jul-2025

... by: Serban

# 654 D7=7 D9=3 F4=5 J2=8 Basics to 29
1. D6=1 solve

2. A7=2 OR H9=2 solve

3. A6=E4=3 solve

4. A2=5 solve

5.F1=C2=6 OR F1=A9=6 solve
Page created on 03-May-2011, last modified on 30-May-2024.
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