by ghfick » Sat Feb 14, 2026 6:57 pm
I tried PhilsFolly. You can get a solution path using Sets and Complex Chains:
Hidden unique rectangle of 46 at r89c39, eliminating 6 from r8c9
Whether 4 at r8c3 or r8c9 is true, the cells at r5c3579 are reduced to 1678, 78, 167 and 1678
Cells at r1368c1 are reduced to 1678, 1678, 678 and 678
1s at r13c1 only ones in row/column => -1 r2c3.
Whether 1 at r1c1 or r3c1 is true, the cells at r4c2369 are reduced to 678, 1678, 678 and 1678
1s at r6c456 only ones in box => -1 r6c8.
Cells at r1257c7 are reduced to 1267, 1267, 16 and 167
Cells at r7c46, r89c5 are reduced to 168, 138, 168 and 36
Cells at r4c2369 are reduced to 678, 1678, 68 and 1678
Whether 4 at r8c3 or r8c9 is true, the cells at r7c46, r89c5 are reduced to 168, 13, 168 and 36
Cells at r267c4 are reduced to 16, 16 and 8
6s at r89c5 only ones in box => -6 r236c5.
Sashimi jellyfish of 1s (r2457\c3679), fin at r2c45, eliminating 1 from r13c6
Naked triplets of 678 at r134c6 => -6 r6c6, -7 r6c6, -8 r6c6
7s at r13c6 only ones in row/column => -7 r23c5.
Sashimi swordfish of 8s (c268\r134), fin at r6c8, eliminating 8 from r4c9
Reverse BUG at r79c47, eliminating 7 from r7c7
7s at r12c7 only ones in row/column => -7 r1c8, r2c9, r3c8.
Naked pairs of 16 at r57c7 => -1 r12c7, -6 r12c7
Finned mutant swordfish of 6s (r52c6\c3b26), fin at r7c5, eliminating 6 from r4c9
Chain with ALS/groups: (1=7)r4c9 - (7)r6c8 = (7-1)r8c8 = (1)r13c8 => -1 r2c9
1s at r2c45 only ones in row/column => -1 r3c5.
1s at r13c8 only ones in box => -1 r8c8.
Discontinuous chain: (6)r6c4 = (6)r2c4 - (6=8)r2c9 - (8)r1c8 = (8-6)r6c8 => -6 r6c8
6s at r5c79 only ones in box => -6 r5c3.
Discontinuous chain: (6)r5c9 = (6)r5c7 - (6=1)r7c7 - (1=3)r7c6 - (3)r7c9 = (3-6)r9c9 => -6 r9c9
Discontinuous chain: (7)r2c3 = (7)r2c7 - (7=2)r1c7 - (2)r1c2 = (2-7)r3c2 => -7 r3c2
Chain with ALS/groups: (7)r2c3 = (7-2)r2c7 = (2)r2c5 - (2=8)r3c5 - (8=7)r5c5 => -7 r5c3
Chain with ALS/groups: (7=1)r4c9 - (1)r8c9 = (1-6)r8c5 = (6-3)r9c5 = (3-7)r6c5 = (7)r5c5 => -7 r5c9
Finned Mutant swordfish of 8s (r52c6\c39b2), fin r4c6, eliminating 8 from r4c3
Discontinuous chain: (1=6)r2c4 - (6=8)r2c9 - (8)r1c8 = (8-7)r6c8 = (7-6)r6c1 = (6-1)r6c4 => -1 r6c4
8s at r13c2 only ones in row/column => -8 r1c1, r2c3, r3c1.
Naked pairs of 67 at r47c2 => -6 r13c2, -7 r1c2
Hidden triples of 167 at r3c1, r3c6 and r3c8
Discontinuous chain: (4=6)r9c3 - (6)r2c3 = (6-8)r2c9 = (8)r5c9 - (8)r5c3 = (8-4)r8c3 => -4 r8c3
X-wing of 7s (c29\r47), eliminating 7 from r4c3
Swordfish of 6s (c168\r138), eliminating 6 from r8c3
Discontinuous chain: (1=6)r3c8 - (6=7)r8c8 - (7)r8c3 = (7-6)r2c3 = (6-8)r2c9 = (8-1)r1c8 => -1 r1c8
Chain with ALS/groups: (1=7)r4c9 - (7=6)r4c2 - (6=7)r7c2 - (7=8)r8c3 - (8=1)r5c3 => -1 r4c3, r5c79
stte
