... by: BGH
Basics 30.92 Step Solution
-- 2 @ H1 37.0
-- 3 @ B2 Solution
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#677, December 20 - December 26, 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). |
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...Tuesday 23-Dec-2025
2 Step Solution
-- 2 @ H1 37.0
-- 3 @ B2 Solution
Sunday 21-Dec-2025
... by: Serban
# 677 A8=8 B9=2 C9=9 basics 251. Number 3 n=3 e=6 N=20 Nc=13 Ns=9 => B2= E7=3 solve
2. Number 6 n=3 e=6 N=21 Nc=18 Ns=1 => C7= E6=6 solve
Note : F8=H2=J9=6
Saturday 20-Dec-2025
... by: Serban
# 677 A8=8 B9=2 C9=9 basics 251. E2=7 & [J3=7 OR G7=7 ]solve
Saturday 20-Dec-2025
... by: Dieter
#677 - initially populated cells: 22 = 27,2 %No solver used, solver = brain.
basics: A8=8, C9=9, B9=2
populated cells: 25 = 30,9 %
Strategy: numbers 8,9,2,3,6,7 occur most frequently, combine two cells.
combinations of G2 = (1,3,7,9) and H3 = (1,8,9)
after basic checks 4 matrices G2/H3 left: 1/9, 3/8, 3/9 and 9/8
G2/H3 = 9/8 solves with G1=3
Optimization:
G1=3 & G2=9 solve.