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#652, June 28 - July 4, 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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Discussion...
Post an idea here...Wednesday 2-Jul-2025
Sunday 29-Jun-2025
... by: Dieter
Sorry, posted solution to old puzzle 553. Please ignore. my comment here.Sunday 29-Jun-2025
... by: Dieter
#553 - populated cells = 22 = 27,2%basics: %
populated cells = 29 = 35,8%
strategy: try to get hidden pairs or triplets. No solver used.
combinations of C2 = (2,5,6,9) and B6 = (1,3,4,6) as numbers 1,3,5,9 are populated most.
C2 = 5 & B6 = 3 solves.
Sunday 29-Jun-2025
... by: Envy E
Following previous comment+5 A3 ( +9 C2 ) +9 C4 +4 B6 +25 C4 C6 +1 C1 +78 C7 C8 ( +2 A8 ) +6 B7 +5 B9
+5 G8 +3 H7 H8 +3 B1 +6 H1 b +5 A1 -5 A3
A3 set to 9 gives a solvable puzzle ( 342 Extreme )
Sunday 29-Jun-2025
... by: Envy E
Begin where Solver runs out of known solutions+3 E1 +9 D2 +1 E2 +7 C2 +7 B7 +7 J3 +2 J1 +8 E1 -3 E1
Saturday 28-Jun-2025
... by: Dieter
#652 - populated cells = 25 = 30,9%basics: %
strategy: try to get hidden pairs or triplets. No solver used.
combinations of F3 = (3,8,9) and F4 = (4,6,9) as numbers 2,3,6,7,8,9 are populated most.
F3 = 3 solves.
Saturday 28-Jun-2025
... by: Serban
# 652 Basics to 251. Column 2 n=3 e=6 Nc=15 Ns=15 => B2=3 solve
2. Number 7 n=3 e=6 N=20 Nc=17 Ns=10 => B7==G4=7 solve
3.Row A n=3 e=6 Nc=40 Ns=1 => A4=5 A9=3 solve
4.Row F n=4 e=5 Nc=7 Ns=3 => F4=4 & [F3=3 OR F2=9] solve