... by: Tomas
Standard methods to 26.D3=1 leads to contradiction, thus E3=1.
Solved with standard methods.
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#687, February 28 - March 6, 2026:
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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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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
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Discussion...
Post an idea here...Saturday 28-Feb-2026
D3=1 leads to contradiction, thus E3=1.
Solved with standard methods.
Saturday 28-Feb-2026
... by: Dieter
#687 - initially populated cells: 25 = 30,9 %No solver used, solver = brain.
basics: B8=5; E5=6
populated cells: 27 = 33,3 %
Strategy: numbers 2,5,1,6,8,9 occur most frequently, combine two cells.
combinations of J1 = (3,4,5,6) and J8 = (3,6,7)
J1/J8 = 4/3 solves.
Saturday 28-Feb-2026
... by: Yves
A3=4 & C4=1Two one-cell solution
Saturday 28-Feb-2026
... by: Serban
# 687 B8=5 E5=6 Basics 271. C4=1 solve
2. A3=4 OR J1=4 OR C9=4 solve
3. B1=9 OR C5=G6=9 solve