The New Sudoku Players' Forum

by **Yogi** » Thu Feb 29, 2024 8:55 pm

7.....4...2..7..8...3..8..9...5..3...6..2..9...1..7..6...3..9...3..4..6...9..1..5

Code: Select all: +---+---+---+ |7..|...|4..| |.2.|.7.|.8.| |..3|..8|..9| +---+---+---+ |...|5..|3..| |.6.|.2.|.9.| |..1|..7|..6| +---+---+---+ |...|3..|9..| |.3.|.4.|.6.| |..9|..1|..5| +---+---+---+

by **yzfwsf** » Fri Mar 01, 2024 1:24 pm

It's really hard.g-Braid[16]

Hidden Text: Show

Code: Select all: Hidden Single: 3 in r9 => r9c8=3 Locked Candidates 1 (Pointing): 4 in b9 => r7c1<>4,r7c2<>4,r7c3<>4 Braid[8]: => r2c6<>6 6r2c6 - 6b5{r4c6=r4c5} - 6r1{r1c4=r1c3} - r9c5{n6=n8} - 8b1{r1c3=r1c2} - r7c5{n8=n5} - r3c5{n5=n1} - 1b1{r3c1=r2c1} - 9b1{r2c1=.} Braid[10]: => r6c5<>8 8r6c5 - 3c5{r6c5=r1c5} - 3r6{r6c5=r6c1} - 9c5{r1c5=r4c5} - 1c5{r4c5=r3c5} - r6c4{n9=n4} - 9c1{r4c1=r2c1} - r2c4{n9=n6} - 6r1{r1c4=r1c3} - 8b1{r1c3=r1c2} - 1b1{r1c2=.} Braid[10]: => r5c1<>4 4r5c1 - r5c6{n4=n3} - 4b7{r9c1=r9c2} - r6c5{n3=n9} - 3b2{r1c6=r1c5} - 4r3{r3c2=r3c4} - r6c4{n4=n8} - r5c4{n8=n1} - r6c2{n8=n5} - r3c2{n5=n1} - 1c5{r3c5=.} g-Braid[10]: => r3c7<>5 5r3c7 - 6b3{r3c7=r2c7} - 7b3{r3c7=r3c8} - 2r3{r3c8=r3c4} - 4r3{r3c4=r3c12} - r2c3{n4=n5} - 5r5{r5c3=r5c1} - 3b4{r5c1=r6c1} - 3c5{r6c5=r1c5} - 5b2{r1c5=r1c6} - 5r8{r8c6=.} g-Braid[12]: => r1c3<>5 5r1c3 - 8b1{r1c3=r1c2} - 6r1{r1c3=r1c456} - 9b1{r1c2=r2c1} - 1b1{r2c1=r3c12} - r3c5{n1=n5} - 5b3{r3c8=r2c7} - 5r5{r5c7=r5c1} - 3b4{r5c1=r6c1} - r6c5{n3=n9} - r6c2{n9=n4} - 4c3{r4c3=r2c3} - 6r2{r2c3=.} Braid[13]: => r5c4<>4 4r5c4 - r5c6{n4=n3} - 1b5{r5c4=r4c5} - 4b2{r2c4=r2c6} - 3b4{r5c1=r6c1} - 4c3{r2c3=r4c3} - 4b6{r4c8=r6c8} - 2b4{r4c3=r4c1} - 2b6{r4c8=r6c7} - r4c8{n2=n7} - 2r9{r9c7=r9c4} - 7b8{r9c4=r8c4} - 7c9{r8c9=r7c9} - 4r7{r7c9=.} Braid[14]: => r2c4<>6 6r2c4 - 6b3{r2c7=r3c7} - 6b1{r3c1=r1c3} - 7b3{r3c7=r3c8} - 8b1{r1c3=r1c2} - 2r3{r3c8=r3c4} - 4c4{r3c4=r6c4} - r5c6{n4=n3} - r6c5{n3=n9} - r6c2{n9=n5} - r5c1{n5=n8} - r5c4{n8=n1} - r1c4{n1=n9} - r1c6{n9=n5} - 5c8{r1c8=.} Braid[13]: => r5c3<>8 8r5c3 - r5c4{n8=n1} - 8b1{r1c3=r1c2} - 9b1{r1c2=r2c1} - r2c4{n9=n4} - 4c3{r2c3=r4c3} - r4c1{n4=n2} - 4r6{r6c1=r6c8} - 2b6{r6c8=r6c7} - 2r9{r9c7=r9c4} - 2r3{r3c4=r3c8} - 7b3{r3c8=r3c7} - 7r9{r9c7=r9c2} - 7c3{r7c3=.} g-Braid[15]: => r2c1<>4 4r2c1 - 4b7{r9c1=r9c2} - 4b2{r2c4=r3c4} - 9b1{r2c1=r1c2} - 9c5{r1c5=r46c5} - r6c4{n9=n8} - r6c2{n8=n5} - r6c7{n5=n2} - r6c8{n2=n4} - 2r3{r3c7=r3c8} - 7b3{r3c8=r3c7} - 7r9{r9c7=r9c4} - 6c4{r9c4=r1c4} - 2c4{r1c4=r8c4} - 2b9{r8c9=r7c9} - 4r7{r7c9=.} g-Braid[16]: => r2c6<>9 9r2c6 - 9b8{r8c6=r8c4} - 9b1{r2c1=r1c2} - 4c6{r2c6=r45c6} - 7b8{r8c4=r9c4} - r6c4{n4=n8} - r5c4{n8=n1} - r2c4{n1=n4} - 4c3{r2c3=r45c3} - r6c2{n4=n5} - r6c7{n5=n2} - r6c8{n2=n4} - 2r9{r9c7=r9c1} - 2b4{r4c1=r4c3} - 4r4{r4c3=r4c6} - 6b5{r4c6=r4c5} - 6r9{r9c5=.} g-Braid[10]: => r2c1<>6 6r2c1 - 6b3{r2c7=r3c7} - 9b1{r2c1=r1c2} - 7b3{r3c7=r3c8} - 1b1{r1c2=r3c12} - 9c5{r1c5=r46c5} - 9c6{r4c6=r8c6} - r3c5{n1=n5} - 5b8{r7c5=r7c6} - 2c6{r7c6=r1c6} - 2r3{r3c4=.} g-Braid[12]: => r6c2<>4 4r6c2 - 4b7{r9c2=r9c1} - 4b1{r3c1=r2c3} - 4b2{r2c4=r3c4} - 6r2{r2c3=r2c7} - 5b3{r2c7=r13c8} - r6c8{n5=n2} - 2r3{r3c8=r3c7} - 2r9{r9c7=r9c4} - 6r9{r9c4=r9c5} - r7c6{n6=n5} - 5r2{r2c6=r2c1} - 5c2{r1c2=.} Braid[11]: => r4c6<>4 4r4c6 - r5c6{n4=n3} - r2c6{n3=n5} - 3b4{r5c1=r6c1} - 4r6{r6c1=r6c8} - 2r6{r6c8=r6c7} - 5r6{r6c7=r6c2} - 5b1{r1c2=r3c1} - 4c1{r3c1=r9c1} - 2r9{r9c1=r9c4} - r7c6{n2=n6} - 6r9{r9c5=.} Braid[4]: => r1c6<>6 6r1c6 - r4c6{n6=n9} - 6c4{r1c4=r9c4} - 7b8{r9c4=r8c4} - 9r8{r8c4=.} Braid[14]: => r7c3<>5 5r7c3 - 5b8{r7c5=r8c6} - 9b8{r8c6=r8c4} - 7b8{r8c4=r9c4} - 9r2{r2c4=r2c1} - 5r2{r2c1=r2c7} - 5r5{r5c7=r5c1} - 3b4{r5c1=r6c1} - r6c5{n3=n9} - r6c2{n9=n8} - r6c7{n8=n2} - 2r9{r9c7=r9c1} - r4c1{n2=n4} - 4c3{r4c3=r2c3} - 6r2{r2c3=.} Braid[14]: => r7c2<>5 5r7c2 - 5b8{r7c5=r8c6} - 9b8{r8c6=r8c4} - 7b8{r8c4=r9c4} - 9r2{r2c4=r2c1} - 7c2{r9c2=r4c2} - 9b4{r4c2=r6c2} - r6c5{n9=n3} - r5c6{n3=n4} - r5c3{n4=n5} - 5r2{r2c3=r2c7} - 5b6{r6c7=r6c8} - 4r6{r6c8=r6c1} - 4c3{r4c3=r2c3} - 6r2{r2c3=.} Whip[13]: => r1c5<>5 5r1c5 - 3c5{r1c5=r6c5} - r5c6{n3=n4} - r2c6{n4=n3} - r2c9{n3=n1} - r1c8{n1=n2} - r1c6{n2=n9} - r2c4{n9=n4} - 4c3{r2c3=r4c3} - 4b6{r4c8=r6c8} - 5c8{r6c8=r3c8} - 5c2{r3c2=r6c2} - 9c2{r6c2=r4c2} - 9c5{r4c5=.} g-Braid[13]: => r3c8<>1 1r3c8 - r2c9{n1=n3} - 7b3{r3c8=r3c7} - 2r3{r3c7=r3c4} - 6b3{r3c7=r2c7} - 4r3{r3c4=r3c12} - r2c3{n4=n5} - r2c6{n5=n4} - r5c6{n4=n3} - 3b2{r1c6=r1c5} - 1c5{r1c5=r4c5} - r5c4{n1=n8} - r5c1{n8=n5} - 5c2{r6c2=.} g-Braid[13]: => r3c7<>1 1r3c7 - r2c9{n1=n3} - 6b3{r3c7=r2c7} - r1c9{n3=n2} - 2b2{r1c4=r3c4} - 4r3{r3c4=r3c12} - r2c3{n4=n5} - r2c6{n5=n4} - r5c6{n4=n3} - 3b2{r1c6=r1c5} - 1c5{r1c5=r4c5} - r5c4{n1=n8} - r5c1{n8=n5} - 5c2{r6c2=.} Braid[14]: => r5c9<>4 4r5c9 - r5c6{n4=n3} - 4c6{r5c6=r2c6} - 3b4{r5c1=r6c1} - 4c3{r2c3=r4c3} - 2b4{r4c3=r4c1} - 9c1{r4c1=r2c1} - r2c4{n9=n1} - 1r5{r5c4=r5c7} - r4c8{n1=n7} - 7b3{r3c8=r3c7} - 6b3{r3c7=r2c7} - r2c3{n6=n5} - 5c7{r2c7=r6c7} - 5c2{r6c2=.} g-Braid[13]: => r4c8<>7 7r4c8 - 7b4{r4c2=r5c3} - 4r5{r5c3=r5c6} - 3r5{r5c6=r5c1} - 5r5{r5c1=r5c7} - 1b6{r5c7=r45c9} - r2c9{n1=n3} - r1c9{n3=n2} - r2c6{n3=n5} - 2b2{r1c4=r3c4} - 4b2{r3c4=r2c4} - r2c3{n4=n6} - 6b3{r2c7=r3c7} - 7r3{r3c7=.} Braid[13]: => r6c1<>9 9r6c1 - r6c5{n9=n3} - 9r2{r2c1=r2c4} - r5c6{n3=n4} - r6c4{n4=n8} - r6c2{n8=n5} - r6c7{n5=n2} - 4b2{r2c6=r3c4} - r3c2{n4=n1} - 2r3{r3c4=r3c8} - 7c8{r3c8=r7c8} - r7c2{n7=n8} - 8b8{r7c5=r9c5} - r9c7{n8=.} g-Braid[8]: => r2c1<>5 5r2c1 - 5c2{r1c2=r6c2} - 9r2{r2c1=r2c4} - 1r2{r2c4=r2c79} - 9r6{r6c4=r6c5} - 3c5{r6c5=r1c5} - r1c9{n3=n2} - r1c6{n2=n5} - r1c8{n5=.} Braid[12]: => r4c1<>4 4r4c1 - 4c3{r4c3=r2c3} - 9c1{r4c1=r2c1} - r2c4{n9=n1} - r2c9{n1=n3} - r2c6{n3=n5} - r3c5{n5=n6} - r9c5{n6=n8} - 6c4{r1c4=r9c4} - r9c1{n6=n2} - 2b4{r6c1=r4c3} - r4c8{n2=n1} - 1r5{r5c7=.} g-Braid[12]: => r6c1<>5 5r6c1 - 5b7{r7c1=r8c3} - 5b6{r6c7=r5c7} - 5r2{r2c7=r2c6} - 4c6{r2c6=r5c6} - 4r6{r6c4=r6c8} - 2r6{r6c8=r6c7} - 3c6{r5c6=r1c6} - 2c6{r1c6=r78c6} - 2r9{r9c4=r9c1} - 2b4{r4c1=r4c3} - 4b7{r9c1=r9c2} - 4r4{r4c2=.} Braid[12]: => r6c1<>8 8r6c1 - 3b4{r6c1=r5c1} - r5c6{n3=n4} - r6c4{n4=n9} - 4r6{r6c4=r6c8} - 9r2{r2c4=r2c1} - r4c1{n9=n2} - 2b6{r4c8=r6c7} - r4c8{n2=n1} - 1b5{r4c5=r5c4} - 2r9{r9c7=r9c4} - 7b8{r9c4=r8c4} - 8c4{r8c4=.} g-Braid[12]: => r1c5<>6 6r1c5 - 3c5{r1c5=r6c5} - 6c4{r1c4=r9c4} - 9c5{r6c5=r4c5} - 1b5{r4c5=r5c4} - 9c1{r4c1=r2c1} - r2c4{n9=n4} - 4c3{r2c3=r45c3} - r6c1{n4=n2} - r4c1{n2=n8} - r4c2{n8=n7} - 7r9{r9c2=r9c7} - 2r9{r9c7=.} Braid[8]: => r1c4<>1 1r1c4 - r5c4{n1=n8} - 6r1{r1c4=r1c3} - 6r2{r2c3=r2c7} - 1b3{r2c7=r2c9} - 1r5{r5c9=r5c7} - 5c7{r5c7=r6c7} - 8r6{r6c7=r6c2} - 8r1{r1c2=.} g-Braid[12]: => r4c2<>4 4r4c2 - 4c3{r4c3=r2c3} - 4c6{r2c6=r5c6} - 6r2{r2c3=r2c7} - 3b5{r5c6=r6c5} - 5r2{r2c7=r2c6} - 3r2{r2c6=r2c9} - 1b3{r2c9=r1c89} - r1c5{n1=n9} - r2c4{n9=n1} - r5c4{n1=n8} - r6c4{n8=n9} - 9c2{r6c2=.} Whip[12]: => r3c8<>2 2r3c8 - 7b3{r3c8=r3c7} - 6b3{r3c7=r2c7} - 5b3{r2c7=r1c8} - r6c8{n5=n4} - 4b5{r6c4=r5c6} - 3b5{r5c6=r6c5} - r6c1{n3=n2} - 2b6{r6c7=r4c9} - 7b6{r4c9=r5c9} - r5c3{n7=n5} - r2c3{n5=n4} - 4r4{r4c3=.} Braid[8]: => r8c4<>2 2r8c4 - 2r3{r3c4=r3c7} - 7b8{r8c4=r9c4} - r9c7{n7=n8} - r6c7{n8=n5} - r9c5{n8=n6} - r7c6{n6=n5} - 5r2{r2c6=r2c3} - 5c2{r1c2=.} g-Braid[9]: => r3c4<>1 1r3c4 - 2r3{r3c4=r3c7} - 4r3{r3c4=r3c12} - 6b3{r3c7=r2c7} - r2c3{n6=n5} - 5c2{r1c2=r6c2} - 5b6{r6c7=r5c7} - 1r5{r5c7=r5c9} - r1c9{n1=n3} - r2c9{n3=.} g-Braid[11]: => r2c9<>1 1r2c9 - r2c1{n1=n9} - 1c4{r2c4=r5c4} - 3r2{r2c9=r2c6} - r2c4{n9=n4} - 3r5{r5c6=r5c1} - 4c3{r2c3=r45c3} - 8r5{r5c1=r5c79} - r6c1{n4=n2} - r6c7{n2=n5} - 5b4{r6c2=r5c3} - 5r2{r2c3=.} Naked Single: r2c9=3 Whip[5]: => r1c5<>1 1r1c5 - 1b3{r1c8=r2c7} - 6b3{r2c7=r3c7} - r3c5{n6=n5} - 5r2{r2c6=r2c3} - 6r2{r2c3=.} Whip[2]: => r4c5<>9 9r4c5 - r1c5{n9=n3} - r6c5{n3=.} Whip[6]: => r7c1<>5 5r7c1 - 5c5{r7c5=r3c5} - r2c6{n5=n4} - r5c6{n4=n3} - r5c1{n3=n8} - r5c4{n8=n1} - 1c5{r4c5=.} Locked Candidates 2 (Claiming): 5 in r7 => r8c6<>5 Braid[8]: => r4c9<>2 2r4c9 - r1c9{n2=n1} - 2b4{r4c1=r6c1} - 3b4{r6c1=r5c1} - r5c6{n3=n4} - r2c6{n4=n5} - r2c7{n5=n6} - r2c3{n6=n4} - 4b4{r4c3=.} Whip[9]: => r1c4<>9 9r1c4 - r1c5{n9=n3} - 3b5{r6c5=r5c6} - 4c6{r5c6=r2c6} - r2c4{n4=n1} - r5c4{n1=n8} - r5c1{n8=n5} - 5b7{r8c1=r8c3} - r2c3{n5=n6} - 6r1{r1c3=.} Whip[4]: => r1c6<>2 2r1c6 - r1c4{n2=n6} - r3c4{n6=n4} - 4b5{r6c4=r5c6} - 3c6{r5c6=.} Locked Candidates 1 (Pointing): 2 in b2 => r9c4<>2 Whip[5]: => r4c3<>8 8r4c3 - r1c3{n8=n6} - r1c4{n6=n2} - 2b3{r1c8=r3c7} - 2r9{r9c7=r9c1} - 2c3{r7c3=.} Braid[8]: => r7c9<>2 2r7c9 - r1c9{n2=n1} - 2b8{r7c6=r8c6} - 4b9{r7c9=r7c8} - 1b9{r7c8=r8c7} - 1r5{r5c7=r5c4} - 1r2{r2c4=r2c1} - 9r2{r2c1=r2c4} - 9r8{r8c4=.} Braid[9]: => r3c4<>6 6r3c4 - r1c4{n6=n2} - r1c9{n2=n1} - 2c9{r1c9=r8c9} - r1c8{n1=n5} - r2c7{n5=n6} - 2b8{r8c6=r7c6} - 5c6{r7c6=r2c6} - r2c3{n5=n4} - 4r3{r3c1=.} Braid[8]: => r8c3<>8 8r8c3 - r1c3{n8=n6} - r1c4{n6=n2} - 6b2{r1c4=r3c5} - r1c9{n2=n1} - 1b2{r3c5=r2c4} - 1r5{r5c4=r5c7} - 1r8{r8c7=r8c1} - 5r8{r8c1=.} Braid[8]: => r7c8<>2 2r7c8 - 2b8{r7c6=r8c6} - 2b7{r8c1=r9c1} - 9b8{r8c6=r8c4} - 7b8{r8c4=r9c4} - r9c7{n7=n8} - 8r8{r8c7=r8c1} - r4c1{n8=n9} - 9r2{r2c1=.} Braid[8]: => r1c3<>6 6r1c3 - r1c4{n6=n2} - 6b2{r1c4=r3c5} - 8c3{r1c3=r7c3} - 1b2{r3c5=r2c4} - r5c4{n1=n8} - 8c1{r5c1=r4c1} - 8c9{r4c9=r8c9} - 2c9{r8c9=.} Hidden Single: 6 in r1 => r1c4=6 Hidden Single: 2 in c4 => r3c4=2 Naked Single: r1c3=8 Locked Candidates 1 (Pointing): 4 in b2 => r2c3<>4 Locked Candidates 2 (Claiming): 4 in c3 => r6c1<>4 g-Braid[7]: => r8c1<>2 2r8c1 - 2b9{r8c7=r9c7} - 2r6{r6c7=r6c8} - 4r6{r6c8=r6c4} - 4b2{r2c4=r2c6} - 5c8{r6c8=r13c8} - 5r2{r2c7=r2c3} - 5r8{r8c3=.} Braid[6]: => r3c1<>5 5r3c1 - 4c1{r3c1=r9c1} - 5b7{r8c1=r8c3} - 5c5{r3c5=r7c5} - 6c1{r9c1=r7c1} - r7c6{n6=n2} - 2b7{r7c3=.} Braid[5]: => r5c3<>7 7r5c3 - 4r5{r5c3=r5c6} - r2c6{n4=n5} - 3r5{r5c6=r5c1} - 5b4{r5c1=r6c2} - 5b1{r1c2=.} Locked Candidates 1 (Pointing): 7 in b4 => r4c9<>7 Whip[5]: => r6c4<>9 9r6c4 - 4b5{r6c4=r5c6} - 4b4{r5c3=r4c3} - 7b4{r4c3=r4c2} - 9b4{r4c2=r4c1} - 9r2{r2c1=.} Whip[5]: => r8c7<>2 2r8c7 - r8c6{n2=n9} - 9c4{r8c4=r2c4} - r2c1{n9=n1} - 1c7{r2c7=r5c7} - 1c4{r5c4=.} Whip[6]: => r8c3<>2 2r8c3 - r8c6{n2=n9} - 9b5{r4c6=r6c5} - 3r6{r6c5=r6c1} - 2b4{r6c1=r4c1} - 9b4{r4c1=r4c2} - 9r1{r1c2=.} Whip[5]: => r9c2<>7 7r9c2 - r9c4{n7=n8} - r9c7{n8=n2} - 2r8{r8c9=r8c6} - 9b8{r8c6=r8c4} - 7c4{r8c4=.} Braid[6]: => r7c9<>7 7r7c9 - 4c9{r7c9=r4c9} - 7b7{r7c2=r8c3} - 4b4{r4c3=r5c3} - 5b7{r8c3=r8c1} - 5r5{r5c1=r5c7} - 7r5{r5c7=.} Braid[5]: => r5c3<>5 5r5c3 - r2c3{n5=n6} - r8c3{n5=n7} - 6b3{r2c7=r3c7} - 7b3{r3c7=r3c8} - 7r7{r7c8=.} Naked Single: r5c3=4 Hidden Single: 4 in c6 => r2c6=4 Hidden Single: 4 in c4 => r6c4=4 Naked Single: r5c6=3 Hidden Single: 3 in r1 => r1c5=3 Hidden Single: 3 in r6 => r6c1=3 Hidden Single: 9 in c5 => r6c5=9 Naked Single: r4c6=6 Locked Candidates 1 (Pointing): 2 in b4 => r4c8<>2 Whip[2]: => r6c7<>5 5r6c7 - 5r2{r2c7=r2c3} - 5c2{r1c2=.} Whip[2]: => r4c1<>8 8r4c1 - r5c1{n8=n5} - r6c2{n5=.} Whip[2]: => r2c7<>1 1r2c7 - r2c1{n1=n9} - r2c4{n9=.} Locked Candidates 1 (Pointing): 1 in b3 => r1c2<>1 Whip[2]: => r4c2<>8 8r4c2 - r5c1{n8=n5} - r6c2{n5=.} Whip[2]: => r1c8<>5 5r1c8 - r1c2{n5=n9} - r1c6{n9=.} Whip[3]: => r7c9<>1 1r7c9 - 1b3{r1c9=r1c8} - r4c8{n1=n4} - 4r7{r7c8=.} Whip[3]: => r9c1<>8 8r9c1 - 2r9{r9c1=r9c7} - r6c7{n2=n8} - 8c2{r6c2=.} Whip[3]: => r5c9<>8 8r5c9 - r6c7{n8=n2} - 2b9{r9c7=r8c9} - 7c9{r8c9=.} Whip[4]: => r5c9<>1 1r5c9 - r1c9{n1=n2} - 2c8{r1c8=r6c8} - 5b6{r6c8=r5c7} - 7r5{r5c7=.} Naked Single: r5c9=7 Braid[4]: => r7c1<>2 2r7c1 - r4c1{n2=n9} - r7c6{n2=n5} - r1c6{n5=n9} - 9r2{r2c4=.} Whip[3]: => r3c1<>6 6r3c1 - 4c1{r3c1=r9c1} - 2b7{r9c1=r7c3} - 6c3{r7c3=.} stte

by **Hajime** » Fri Mar 01, 2024 5:37 pm

This is a T&E(2) right? Only solvable bij computer programs?

by **yzfwsf** » Fri Mar 01, 2024 11:27 pm

Yes, it's T&E(Single,2), but it's also T&E(LC,1).

by **m_b_metcalf** » Sat Mar 02, 2024 12:13 pm

Such diagonal patterns have been well explored, for instance in Patterns Game 16. It's not difficult to find quite hard examples using your pattern, such as these:

Code: Select all: 1 . . . . . 2 . . . 3 . . 4 . . 5 . . . 6 . . 5 . . 7 . . . 8 . . 1 . . . 4 . . 7 . . 6 . . . 8 . . 2 . . 5 . . . 9 . . 5 . . . 2 . . 3 . . 9 . . . 7 . . 6 . . 3 Harder 1.....2...3..4..5...6..5..7...8..1...4..7..6...8..2..5...9..5...2..3..9...7..6..3 1 . . . . . 2 . . . 3 . . 4 . . 5 . . . 6 . . 5 . . 7 . . . 8 . . 4 . . . 9 . . 7 . . 6 . . . 8 . . 2 . . 5 . . . 1 . . 9 . . . 2 . . 3 . . 8 . . . 7 . . 6 . . 3 Yet Harder 1.....2...3..4..5...6..5..7...8..4...9..7..6...8..2..5...1..9...2..3..8...7..6..3

Mike

by **shye** » Tue Sep 10, 2024 12:11 pm

hard puzzles are just tiresome unless they have interesting interactions (well, to me at least)
this pattern can be made into enjoyable puzzles, why not post one of those?

Code: Select all: +-------+-------+-------+ | 1 . . | . . . | 5 . . | | . 2 . | . 7 . | . 4 . | | . . 3 | . . 1 | . . 9 | +-------+-------+-------+ | . . . | 4 . . | 8 . . | | . 7 . | . 5 . | . 2 . | | . . 1 | . . 2 | . . 3 | +-------+-------+-------+ | . . . | 8 . . | 6 . . | | . 4 . | . 2 . | . 7 . | | . . 9 | . . 3 | . . 8 | +-------+-------+-------+ 1.....5...2..7..4...3..1..9...4..8...7..5..2...1..2..3...8..6...4..2..7...9..3..8

by **P.O.** » Tue Sep 10, 2024 5:22 pm

basics:

Hidden Text: Show

Code: Select all: 1 689 47 269 3689 469 5 368 27 5689 2 568 3569 7 5689 13 4 16 47 568 3 256 468 1 27 68 9 2569 3569 256 4 13 679 8 1569 567 3689 7 468 13 5 689 19 2 146 4569 5689 1 679 689 2 47 569 3 25 135 257 8 19 4579 6 39 24 3568 4 568 1569 2 569 39 7 15 2567 156 9 567 146 3 24 15 8 5r4c9 => r8c467 <> 9 r4c9=5 - c9n7{r4 r1} - c9n2{r1 r7} - r7c1{n2 n5} - c3n5{r78 r2} - c6n5{r2 r8} r4c9=5 - r8c9{n5 n1} - c4n1{r8 r5} - r5c7{n1 n9} - r6c8{n59 n6} - r5c9{n16 n4} - r6c7{n4 n7} - r6c4{n67 n9} | r8c7<>9 => r4c9 <> 5 ste.

by **eleven** » Tue Sep 10, 2024 7:57 pm

If r7c1 would be 5, you could reflect the puzzle at the diagonal to get the same. Then you can reflect a solution (which must be a valid grid too), to get another solution for the same puzzle (which cannot be the same).
So -5r7c1, and it can be solved with 2 swordfish (or 3-strong-links).

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