SudokuWiki.org
Strategies for Popular Number Puzzles
9x9 Solvers
6x6 Solvers
Weekly 'Unsolvable'
Puzzles to Play
Apps
Str8ts
Other
#674, November 29 - December 5, 2025:
|
|
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.Share and Enjoy
Supporter Members have access to all these puzzles going back to number 1.
Discussion...
Post an idea here...Saturday 29-Nov-2025
Saturday 29-Nov-2025
... by: Yves
A1=6 & E=2 SolveSaturday 29-Nov-2025
... by: Dieter
#674 - initially populated cells: 24 = 29,6%No solver used, solver = brain.
basics: H1=4
populated cells: 25 = 30,9%
Strategy: Numbers 4,2,5,6,9 occur most frequently, combine two cells.
combinations of G5 = (5,6,9) and G9 = (1,6,7,9)
3 matrices left after basic checks: G5/G9 = 5/6, 6/9 and 9/1
G5/G9 = 5/6 solve with B8=5
Optimization:
B8=5 & G9=6 solve.
Saturday 29-Nov-2025
... by: Serban
# 674 H1=4 Basics to 251. Column 2 n=4 e=5 Nc=7 Ns=3 => D2=7 solve
Note: H2=2
2. Box 3 ABC123 n=3 e=6 Nc=10 Ns=3 => H3=6 & [G3=1 OR J2=5] solve
3. Number 2 n=3 e=6 N=21 Nc=13 Ns=12 => B3 & [D4 OR E1]=2 solve
Note: H2=2