... by: Serban
# 647 C1=9 F9=7 H7=8 Basics to 281. Number 9 n=5 e=4 N=10 Nc=5 Ns=5 => E8=9 solve
2. Box 6 GHJ456 n=3 e=6 Nc=42 Ns=11 => J5=1 & G4=6 solve
Note: G4=6 H4=4
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#647, May 24 - May 30, 2025:
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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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Post an idea here...Saturday 24-May-2025
1. Number 9 n=5 e=4 N=10 Nc=5 Ns=5 => E8=9 solve
2. Box 6 GHJ456 n=3 e=6 Nc=42 Ns=11 => J5=1 & G4=6 solve
Note: G4=6 H4=4
Saturday 24-May-2025
... by: Hrudaya
F1=1Saturday 24-May-2025
... by: Billa
Solved in four steps:Kraken Ring: [(1)r9c8 = r9c5 - (1=3586)b5p4568 - (6=391)r125c8-] = (1-9)r9c7 = r56c7 - (9)r5c8 = [(3=6)r5c8 - (6=1583)b5p4568-] => r147c5<>1, r5c237<>3
This almost-ring (1)r9c8 = r9c5 - (1=3586)b5p4568 - (6=391)r125c8- is valid save for (1)r9c7, which ends up making an ALS-XZ Ring using the same b5 ALS. Quite a lot of shared eliminations.
ALS-AIC: (8)r2c2 = r5c2 - (8=3569)r5c4568 - (9=3)r2c8 => r2c2<>3
XY-Wing: r1c5 & r35c4 => r2c4, r4c5<>6
Finned X-Wing: (6)r47 => r8c6<>6
STTE