The New Sudoku Players' Forum

[Eioru]

Ask for 17-clues puzzles
Does it have Diabolical one, I feel many of them are easy to solve by hidden or naked single?

[ravel]

There was a list around with 450 harder puzzles out of the 36000 filterted by Eppstein, which i scanned for my hardest thread (none qualified), with still many of them solvable with coloring/nishio, but i cannot find a link now.

[ravel]

The puzzles from JPF were rated with 4,5 and 3 steps,
the ones by Claudi and Eioru were solved with less than 4.

[Eioru]

Collect all on Sep 27
10.0

Code: Select all

.....1..2.1..2..3.4..5.......4.....6.7..3..1.8.....9..5....8.......1..7...64..5..

9.9

Code: Select all

.....1..2.1..3..4.5..6.......4.....1.7..8..3.2.....6..9....2.......4..7...35..8..
.....1..2.1..3..4.5..6.......4.....1.7..8..3.2.....9..9....2.......4..7...35..8..
..1.....2.3..4....5..6..3....7..8..1.6..1..3.1..9..8....5..9..4.8..5..7.2..1..9..
..1..2..3.2..4..1.5..6..........7..1.3..8..2.4..5..6....5..9..2.7.....8.3.....9..
.1..2...3......41........5...56......2..4...78....9...6....3....4..1...2..95.....
1.......2.3..4..5...6...7.....1.3....4..6..8....4.5.....2...9...5..3..4.7.......1
1.......2.3..4..5...6...7.....1.3....4..8..9....4.5.....7...1...8..3..4.2.......6
1.......2.3..4..5...6...7.....1.3....8..7..4....4.6.....2...6...5..3..8.9.......1
1.......2.3..4..5...6...7.....1.4....8..7..4....5.8.....7...6...5..3..8.2.......1
1....23...4..5......26....7..7.....6.8.....2.9.....5..5....31......9..4...47....8


9.8

Code: Select all

.....1..2.3..4..5.6..2.......5.....3.7..8..4.2.....9..9....4.......5..7...41..6..
.....1..2.3..4..5.6..7.......5.....4.8..2..9.7.....3..1....4.......5..8...96..7..
..1...2...3..4..5.6.......7...1.3....8.....3....6.4...2.......6.4..5..8...7...1..
..1..2..3.2..4....5..6..2....7..8..1.3.....2.1..9..6....9..7..4.8.....5....1..7..
1.......2.3..4..5...6...7.....1.3....4..6..8....9.4.....7...1...5..9..3.2.......6
1.......2.3..4..5...6...7.....1.3....8..7..3....5.8.....7...6...5..3..8.2.......1
1.......2.3..4..5...6...7.....1.3....8..7..3....9.4.....7...1...4..5..8.2.......9
1.......2.3..4..5...6...7.....1.4....4..7..8....9.5.....7...6...5..9..3.2.......1
1.......2.3..4..5...6...7.....1.4....8..7..4....5.3.....2...6...4..5..3.7.......1
1.......2.3..4..5...6...7.....1.4....8..9..4....5.8.....2...1...5..3..8.7.......6
1.....2...3..1..4...5..4..6...7..5...8..3..6...9..1..8...5..6...5..2..8...6..9..7
1..2..3......4......5..6..22..7..1...8.....6...9..3..77..3..4......8......8..5..9

9.7

Code: Select all

.....1..2.3..2..4.5..6.......6.....5.7..4..8.1..8..9..7....2.......3..1...89..6..
..1...2...3.....4.5...6...7...1.8.....4.3.8.....9.4...6...2...3.7.....5...9...1..
1.......2.2..3..4...5...6.....3.7....4..1..3....8.5.....8...5...3..2..9.6.......1
1.......2.3..4..5....6.7.....4...6...7..8..4...9...8.....9.8....2..7..1.5.......3
1.......2.3..4..5...6...7.....1.3....8..5..4....4.9.....7...1...4..3..8.2.......6
1.......2.3..4..5...6...7.....1.3....8..6..3....9.4.....7...1...4..5..8.2.......9
1.......2.3..4..5...6...7.....1.4....8..6..3....9.3.....7...1...4..5..8.2.......9

9.6

Code: Select all

..1...2...3..4..5.6.......7...1.5....4.....8....9.4...7.......6.5..3..4...2...1..
1.......2.3..4..5...6...7.....1.3....4..6..8....4.5.....2...9...8..5..4.7.......1
1.......2.3..4..5...6...7.....1.4....5..2..4....5.3.....2...6...4..8..3.7.......1
1.......2.3..4..5...6...7.....1.4....5..3..8....5.6.....7...1...2..5..3.9.......6
1.......2.3..4..5...6...7.....1.5....8..6..4....9.4.....7...1...5..3..8.2.......9

9.5

Code: Select all

.....1....1..2..3.4..5..1....6..7..3.8..3..1.2..9..4....9.....2.7..8..6.8..3..5..
.....1..2.3..4..5.6..2.......5.....7.7..3..4.2.....6..1....8.......7..9...46..8..
.....1..2.3..4..5.6..7.......5.....4.7..8..3.2.....6..1....6.......5..7...39..8..
..1.....2.3..4..5.6..7..........8....2..3..4.9..6..7....6.......4..1..3.8.....9..
1.......2.3..4..5...6...7.....1.3....4..2..3....5.4.....7...6...5..8..4.2.......1
1.......2.3..4..5...6...7.....1.3....4..7..8....4.5.....7...6...8..5..3.2.......1
1.......2.3..4..5...6...7.....1.3....5..7..4....4.8.....2...1...4..8..3.7.......6
1.......2.3..4..5...6...7.....1.3....5..7..8....5.4.....7...6...4..5..3.2.......1
1.......2.3..4..5...6...7.....1.4....8..2..4....5.8.....2...6...4..3..8.7.......1
1.2...3.....4.5...6.........7.....483...2.......5...9..9.8....7....1.6...........


9.4

Code: Select all

.....1..2.1..3..4.5..6.......4.....1.7..8..3.6.....8..2....6.......5..7...39..5..
.....1..2.1..3..4.5..6.......7.....8.9..4..1.8.....5..6....2.......1..9...87..3..
.....1..2.3..2..4.5..6.......3.....7.1..8..2.4..7..5..6....4.......6..1...73..9..
.....1..2.3..2..4.5..6.......4.....7.8..3..2.9.....5..1....9.......4..8...75..9..
.....1..2.3..2..4.5..6.......7.....3.1..4..8.6.....5..9....6.......7..3...85..9..
.....1..2.3..4..5.1..6.......5.....7.8..3..4.6.....1..9....6.......5..7...42..9..
.....1..2.3..4..5.6..7.......4.....8.9..5..3.8.....6..1....7.......3..9...82..4..
...1..2...3..4..5...4..6..78..3..5...7.....6...2..7..96..2..4...1..5..2...8..9...
..1.....2.3..4....5..6..3....4..7..1....8..3.9..2..6.......8..9.7..2..4.2..1..8..
..1.....2.3..4....5..6..7....8..7.......1..3.7..5..6....5..9..4....5..8.2..3..9..
..1...2...3..4..5.6.......7...1.3....8.....3....6.8...7.......6.5..3..4...2...1..
..1..2..3.2..3..4....5..6.......4..2.7..5..8.9..3..1....8.......5..6..7.7..9..3..
..1..2..34..5..6...7..3..8...8..1..61..2..3...5.....1...2..4..97..9..4......6..3.
1...2.......3.1.....4.5..6.........763......5.8274.....4..6..8..5....1..2....9.5.
1..2..3......4..5...2..6..77..8..5...8.....6...9..3..49..3..6...5..9..2...1..7..5

9.3

Code: Select all

.....1..2.2..3..4.5..6.......7.....6.8..4..3.9..8..7..8....9.......2..7...57..1..
.....1..2.2..3..4.5..6.......7.....8.9..4..2.6..8..5..9....8.......9..3...67..1..
...1..2...2..3..1...4..5..36.....5...7..8......3..7..69..4..6...8..9..2...2..8..4
...1..2...2..3..4...5..6...6..2..7...8.....9...3..7..65..8..4...7..9..8...9..5...
..1.....2.3.....1.4..5..3....3..6..1.7..8..3.9..4..5.......8..9.6..4..2.7..1..8..
..1.....2.3..4..1.5..6..3....7..8..1.2..1..8....5..6....5..9....4..3..7.8.....9..
..1..2..3.2..4..1.5..6..2.......7....8..1..2.4..5..6....5..9..8.7.....4.8.....9..
..1..2..32..4..5......6..1...3..7..18..5..9...4..9..2...8.....24..3..1...6.....7.
1..2..3......1......4..5..67..8..2...4.....9...9..3..13..1..8......7......6..9..5
1..2..3......4......5..1..62..3..1...7.....8...9..6..24..1..7......9......7..5..9
1..2..3......4......5..6..75..8..4...9.....1...3..7..64..9..5......8......6..2..9
1..2..3......4..5...6..5..17..8..2...1..9......2.....38..7..9...7.....3...3..6..5
1..2..3...4.....5...5..6..77..6..8...1..7..2...4..3..65..3..1......9..7...9..8...
1..2..3...4..5..2......6..73.....8...7.....1...6.....97..1......2..4..5...9..3..6
1..2..3...4..5..2...6..7..48..6..9...1..9..4......5..79.....2...3..6..1......8..9
1..2..3.4.....5.1...631...27.28...3...3.7.4...6...37.86...392...3.4.....2.5..1..3


9.2

Code: Select all

..........1..2..3...4..3..5...6..4...2..7..8...8..4..9...1..7...9..8..1...6..5..2
.....1..2.2..3..4.5..6.......3.....7.8..4..2.6..7..9..8....6.......5..8...59..3..
.....1..2.3..2..4.5..3.......6.....5.7..4..2.8..9..7..7....8.......9..8...16..3..
...1...2...3.4.5...6......7...8...1...2.5.8...7...4..64..58......8.2.9...9...6...
...1..2...3..4..5......6..76.....1...4..8..3...9.....59..7......8..3..4...2..9...
..1.....2.3..4..5.2..6.......7..5..8.6..1..2.9..7..1....4.....6....8..3.7..9..8..
..1.....2.3..4..5.6..7..........3....2..5..8.7..6..1....6.......5..8..3.9.....4..
..1..2..3...4..5...5..6..2..1....7..7..8.3..6..47...8..3..7..9...7..5..29..3..8..
1..2..3......1......2..4..53..6..7...5.....8...9..5..26..3..5......7......8..9..4
1..2..3......4......2..5..67..8..4...3.....1...5..6..29..1..7......8......7..9..5
1..2..3......4......4..5..63..1..7...5.........8..4..52..7..1.............6..9..8
1..2..3......4......5..6..13..7..8...9.....2...4..2..79..1..7......5......6..8..4
1..2..3......4......5..6..47..3..1...8.........6..4..93..7..2.............9..8..5
1..2..3......4......5..6..77..6..2...8.....9...4..3..59..3..8......5......6..7..1
1..2..3...2..4..5...5..6..27.....8...5..6..7...3..9..59..8..4...4..3..2......1..7
1..2..3...4..5..6......6..73.....8...8.....1...9.....27..6......5..4..8...2..3..9

9.1

Code: Select all

..........1..2..3...4..5..6...1..5...4..7..6...8..9..4...5..8...2..1..7...3..2..9
......1.2..3....4..56....7.7..8.2....2...1..6....4.9...9...5.6.5.2.98....7..1....
...1...2...3.4.5...6......74..8...1...2.5.....7...4..63..58......8.2.9...9...6..8
...1.2.....34.51...6..7..5.31.....4...4...6..28.....73.9..5..1...57.69.....9.8...
1.....2...3...4.5...2.6...1...3...7...6...8...5...8...2...1.9...7.5...8...3.....4
1...2...3.4...5.6...784.......4.2.7....6..2.1....576..47....9..9.3....1..51.....6
1..2..3......1......4..5..63..4..7...8.....2...9..6..57..8..6......3......3..4..9
1..2..3......3..4...5..4..63..7..8...6.....9...7..8..42..9..7.........8...1..5...
1..2..3......4......3..5..67..4..6...5.....2...6..8..92..1..8......9......8..6..7
1..2..3......4......4..5..67..3..8...4.....2...5..7..96..1..2......6......9..8..5
1..2..3......4......4..5..67..3..8...9.....5...6..1..92..9..7......8......5..7..3
1..2..3......4......5..1..64..7..8...3.....2...6..2..97..3..9......8......9..6..1
1..2..3......4......5..6..78..1..2...7.....1...9..8..53..8..5......6......4..5..9
1..2..3......4......5..6..78..7..1...3.....8...6..5..42..6..5......9......4..8..6
1..2..3......4......5..6..78..9..2...7.....4...1..8..64..3..8......2......6..5..3
1..2..3...3..4..5...4..6..24.....7...7.....3...1.....58..1..9...6..5..8...9..7..6
1..2..3...4..3..5...6.....44..6..7...7..2..6...8..7..17..1..6...9..8..2......2..3
1..2..3...4..5..1...6..7..83.....5...8.....7...9.....67..6..9...9..1..4...2..3..5
1..2..3...4..5..6...5..7..89.....7...1.....2...8.....33..5..4...6..2..1...1..8..9
1..2..3...4..5..6...7..8...3..5..7...1.....4...5.....97..6..1...6..2..9...8..1..7
1.23........4..5...5...6..7..5.3..8......8..986..7.3..6..8...5...1..3...3...9.4.6


9.0

Code: Select all

..........1..2..3...4..3..5...5..3...4..6..2...7..8..9...2..6...6..9..7...3..4..8
..........1..2..3...4..3..5...6..7...4..8..6...9..5..2...4..8...2..6..7...5..2..1
..........1..2..3...4..5..2...2..5...6..7..1...8..3..4...6..7...3..5..9...2..4..8
..........1..2..3...4..5..6...4..5...7..6..8...9..8..4...1..2...2..3..7...6..9..5
....1..23.4.5......3...61...7..6....8.345..1...1..8..47..6..3...6..8.........259.
...1...2...3.4.5...6......74..8...1...2.5.....7...4..63..58......8.2.9...9...6..2
...1..2....2..3.4..56...7.35...2..8....5.7....6..4...56.9...83..7.2..1....3..6...
...1.2.....34......5..6..7.31.....48..4...5..29......3.8..7..1...76.58.....8.9...
..1...2...2.3.4.5.4.......6.7..1..2....8.6....5..3..6.2.......9.3.7.9.8...8...4..
..1.2...34...5.......6.4.7..8....9....48692....3....6..2.5.1.......9...57...4.8..
1.........2..3..4...5..6..2...6..7...8..7..9...4..2..8...9..6...3..6..7...2..5..1
1.........2..3..4...5..6..7...2..7...8..7..5...4..5..8...3..1...5..4..2...9..1..6
1.....2...3...4.5...6.7...4...5...6...2.4.7...8...3...4...9.6...2.1...8...7.....9
1..2..3......1......4..5..62..7..5...5.....8...7..8..49..3..2......9......6..4..9
1..2..3......1......4..5..63..7..8...1.....4...9..8..57..3..6......8......2..4..9
1..2..3......4......2..5..63..7..8...5.....4...7..9..24..8..6......3......9..7..1
1..2..3......4......3..5..62..1..7...8.....9...6..8..44..9..2......8......5..3..7
1..2..3......4......4..3..53..6..1...7.....2...8..9..46..7..2......5......9..8..1
1..2..3......4......4..5..26..1..7...8.....4...5..8..97..3..9......1......2..7..5
1..2..3......4......5..1..64..1..2...3.....7...6..8..59..7..4......9......7..6..3
1..2..3......4......5..1..67..8..2...3.....5...4..9..78..6..7......1......9..5..4
1..2..3......4......5..1..67..8..4...6.....1...1..9..24..9..2......7......8..5..9
1..2..3......4......5..3..62..1..7...8.....5...4..6..89..7..1......9......3..4..5
1..2..3......4......5..3..62..7..4...8.....1...6..9..59..8..2......7......1..5..4
1..2..3......4......5..3..62..7..4...8.....3...1..9..57..1..8......2......6..5..9
1..2..3......4......5..3..64..7..8...3.....5...6..9..77..8..1......1......2..6..9
1..2..3......4......5..3..66..7..2...7.....5...8..9..42..1..9......6......7..4..8
1..2..3......4......5..6..12..7..4...6.....1...4..8..79..3..2......9......7..5..8
1..2..3......4......5..6..17..3..8...6.....5...4..9...3..9..2......8......7..5..9
1..2..3......4......5..6..24..3..7...8.....6...1..5..98..7..2......3......6..9..1
1..2..3......4......5..6..27..8..2...3.....5...4..7..62..1..9......8......9..5..4
1..2..3......4......5..6..43..1..7...2.....8...9..8..56..4..9......7......8..5..7
1..2..3......4......5..6..45..7..1...4.....6...8..2..37..6..2......9......9..5..8
1..2..3......4......5..6..72..6..8...7.....2...4..8..93..7..6......1......9..5..4
1..2..3......4......5..6..73..6..2...8.....1...7..1..92..8..9......7......6..4..5
1..2..3......4......5..6..73..6..8...4.....5...9..5..68..3..9......7......1..2..4
1..2..3......4......5..6..73..8..1...7.....5...6..7..49..5..8......9......1..4..2
1..2..3......4......5..6..73..8..9...8.....7...6..5..12..3..4......6......9..7..8
1..2..3......4......5..6..74..3..8...8.....7...6..9..53..8..9......2......2..5..1
1..2..3......4......5..6..74..6..8...7.....1...9..5..32..8..5......2......6..7..9
1..2..3......4......5..6..75..1..8...8.....2...6..5..48..9..2......3......7..2..6
1..2..3...4..5..1...6..7..53.....8...2.....4...7.....97..1..6...5..4..7...8..9..3
1..2..3...4..5..1...6..7..88.....9...5.....7...9.....32..3..7...7..6..4...8..2..5
1..2..3...4..5..6...3..7..58.....9...9.....7...1.....62..1..6...1..4..9...4..5..7
1..2..3...4..5..6...7.....55..8..9...6..7..3...4..1..29..3..4...7..8..2......4..8
1..2..3...4..5..6...7..6..84.....2...9.....8...1.....73..9..8...6..2..5...4..8..1
1..2..3...4..5..6...7..8...3..5..7...1.....4...5..6..97.....1...6..2..9...8..1..7
1..2..3...4..5..6...7..8..28.....7...3.....4...6.....59..3..4...5..7..2...1..9..8
1..2..3...4..5..6...7..8..99.....2...3.....4...6.....18..6..7...5..4..1...3..2..8
1..2.3..4.4.....5...6...1.....7.4..2.........2..8.1..6..5...9...3.....8.8..1.9..7


[ronk]

Collect all on Sep 25

Thanks for the collection. All the puzzles are different (no equivalents) ... but of the 156 puzzles, #52 thru #155 are not minimal.

[edit: puzzle with invisible character no longer exists]

[Eioru]

Code: Select all

 . . 2 | . . . | 9 . .
 . 9 . | 3 . 1 | . 7 .
 1 . . | . . . | . . 8
-------+-------+-------
 . 6 . | . 2 . | . 9 .
 . . . | 5 . 8 | . . .
 . 7 . | . 3 . | . 8 .
-------+-------+-------
 9 . . | . . . | . . 4
 . 3 . | 6 . 4 | . 5 .
 . . 5 | . . . | 1 . .

I find out this kind has quite a few of solving methods.
Like this 9.0 puzzle.
1 x Naked Single
6 x Pointing
2 x Claiming
2 x Naked Pair
1 x X-Wing
2 x Hidden Pair
1 x Naked Triplet
1 x Swordfish
1 x XYZ-Wing
1 x Unique Rectangle type 1
4 x Turbot Fish
7 x Forcing Chain
4 x Region Forcing Chains
4 x Cell Forcing Chains
7 x Dynamic Cell Forcing Chains
4 x Dynamic Region Forcing Chains
2 x Dynamic Contradiction Forcing Chains
except hidden single.
This has 45 methods in 16 kinds (2.81 per kind)

[Eioru]

Code: Select all

1..2..3.4
.....5.1.
..631...2
7.28...3.
..3.7.4..
.6...37.8
6...392..
.3.4.....
2.5..1..3

[tarek]

This would probably mke the list (I hope)

Code: Select all

 6 . . | . . 1 | 9 . . 
 . 8 . | . 3 . | . . . 
 . . 1 | 7 . . | . . 2 
-------+-------+------
 . . 2 | . . . | . . 7 
 . 5 . | . . . | . 1 . 
 4 . . | . . . | 3 . . 
-------+-------+------
 3 . . | . . 9 | 6 . . 
 . . . | . 4 . | . 8 . 
 . . 8 | 2 . . | . . 5

tarek

[Eioru]

Code: Select all

 6 . . | . . 1 | 9 . . 
 . 8 . | . 3 . | . . . 
 . . 1 | 7 . . | . . 2 
-------+-------+------
 . . 2 | . . . | . . 7 
 . 5 . | . . . | . 1 . 
 4 . . | . . . | 3 . . 
-------+-------+------
 3 . . | . . 9 | 6 . . 
 . . . | . 4 . | . 8 . 
 . . 8 | 2 . . | . . 5

tarek

I normalize it
1....23...4..5......26....7..7.....6.8.....2.9.....5..5....31......9..4...47....8
It is 9.9 ~~ so hard
and has same use-times Dynamic Contration Forcing Chains(36) as this one
..1.....2.3..4....5..6..3....4..7..1....8..3.9..2..6.......8..9.7..2..4.2..1..8..

[tarek]

I really haven't checked my puzzles if they were isomorphic versions of others posted in this thread .

I noticed from an earlier post by gsf that they are not... I checked both of these puzzles & they come from different canonical grids. So pending a further check, I think the puzzle was not posted before

tarek

[ronk]

This would probably mke the list (I hope)

Code: Select all

 6 . . | . . 1 | 9 . . 
 . 8 . | . 3 . | . . . 
 . . 1 | 7 . . | . . 2 
-------+-------+------
 . . 2 | . . . | . . 7 
 . 5 . | . . . | . 1 . 
 4 . . | . . . | 3 . . 
-------+-------+------
 3 . . | . . 9 | 6 . . 
 . . . | . 4 . | . 8 . 
 . . 8 | 2 . . | . . 5

tarek

tarek, very nice puzzle. With a Sudoku Explainer rating of 9.9, it should have an excellent chance of making ravel's list. It is a variant of Ocean's "diagonal" pattern posted here and here.

Code: Select all

 . . * | . . * | . . *
 . * . | . * . | . * .
 * . . | * . . | * . .
-------+-------+-------
 . . * | . . * | . . *
 . * . | . * . | . * .
 * . . | * . . | * . .
-------+-------+-------
 . . * | . . * | . . *
 . * . | . * . | . * .
 * . . | * . . | * . .


Your puzzle permuted by

• rotating 90 degrees clockwise
• swapping rows 4 & 6
• swapping cols 4 & 6

Code: Select all

 . . 3 | . . 4 | . . 6
 . . . | . 5 . | . 8 .
 8 . . | 2 . . | 1 . .
-------+-------+-------
 . . 9 | . . . | . . 1
 . 4 . | . . . | . 3 .
 2 . . | . . . | 7 . .
-------+-------+-------
 . . 6 | . . 3 | . . 9
 . 8 . | . 1 . | . . .
 5 . . | 7 . . | 2 . .


AFAICT none of Ocean's diagonal puzzles -- even when minimalized -- have an empty 3x3 box.

From a pattern viewpoint, your puzzle should stand on its own. However, from the POV of puzzle hardness I think your puzzle should be "normalized" (permuted) to Ocean's five-slash-diagonal pattern. Does that make any sense to anyone else?

[Ocean]

This would probably mke the list (I hope)

Nice and hard puzzle, with a nice double diagonal symmetry! Fine to see a new ER-9.9.

From a pattern viewpoint, your puzzle should stand on its own. However, from the POV of puzzle hardness I think your puzzle should be "normalized" (permuted) to Ocean's five-slash-diagonal pattern. Does that make any sense to anyone else?

It's correct that the pattern can be classified among the 'diagonal patterns', found in several from 'top1465', and examined by gfroyle, ruud, tso, myself and others. But I can not recall any of those - on the hardest list - with an empty box except two of tarek's own previous puzzles (equivalent pattern). The double diagonal mirror symmetry is also rare among these puzzles.

[tarek]

tarek, very nice puzzle. With a Sudoku Explainer rating of 9.9, it should have an excellent chance of making ravel's list.?

Thanx, I've noted several SE9.9 which didn't require many steps.

Nice and hard puzzle, with a nice double diagonal symmetry! Fine to see a new ER-9.9.
.....

It's correct that the pattern can be classified among the 'diagonal patterns', found in several from 'top1465', and examined by gfroyle, ruud, tso, myself and others. But I can not recall any of those - on the hardest list - with an empty box except two of tarek's own previous puzzles (equivalent pattern). The double diagonal mirror symmetry is also rare among these puzzles.

Thanx, I have tried to change the pattern a bit & forgot that it gives the same pattern when permuted.......I tried to stick with the empty box & symmetry as I've noted none on the list. I should have figured that by default that means that they shouldn't be isomorphs of puzzles on the list anyway .

The number quoted by Ocean (around 1,000,000) for generated puzzles is just beyond me.......I was trying to find a way around that & i probably got lucky.......

tarek

[ravel]

What a puzzle, Tarek !

When first got stuck, my program could only eliminate 3 of 222 candidates. The best solution found needed 20 steps (and no other with 20).
Amazingly my program is much faster than for other puzzles, because so few eliminations are possible.

I keep the original version that Tarek posted in the list, because my programs solution refers to this.

[Added: gsf-rating 99639, i.e. nr 10 in this list]

[Eioru]

1-day-product

Code: Select all

1..2..3......1......3..4..52..6..4...7.....8...8..3..99..4..2......6......5..8..7
1..2..3......1......4..5..67..8..2...5.....7......9..43..7..1......6......8..4..9
1..2..3......3......4..1..56..7..1.........8...8..9..47..6..2......1......5..8..9
1..2..3......3......4..1..56..7..1...7.....8...8..9..47..6..2......1......5..8..9
1..2..3......3......4..5..67..1..8...2.....7...6..9..5...3..7......8......9..6..4
1..2..3......3......4..5..67..1..8...2.....7...6..9..56..3..7......8......9..6..4
1..2..3......4.........5..64..3..7...7.....2...5..8..92..1..8......9......8..6..4
1..2..3......4......2..5..62..7..1...8.....2...5..6..94..8..9......3......7..9..5
1..2..3......4......5..6..72..3..7...8.....9...1..8..64..7..5......3......6..9..1
1..2..3......4......5..6..73..7..8...2.....6...9..1...8..3..2......9......6..5..4
1..2..3......4......5..6..73..7..8...2.....6...9..1..38..3..2......9......6..5..4
3..4..2......9......5..7..39..2..4...6.....1...1..5..7...3..5......4......7..6..8
4..8..5......7......1..6..23..9..4...1.....3...7..3..69..5..2......4......2..8..7
5..9..1......4......3..8..79..2..7...3.....8...8..4..62..1..9......2......4..6..5
7..5..3......9......8..1..52..3..5...8.....9...1..7..66..2..4......8......7..5..1
8..3..1......5..2......2..86..9..4...8..7......5..1..64..7..2...9..3..1...6..9..5
9..6..4......2......8..1..35..4..9...3.....2...6..5...7..9..5......7......2..8..1

The 10th puzzle is amaze to me that it has all chains without (+).
Last 6 puzzles is rated lower than 9.0, but I hope they can challenge to become higher than 4 steps.
And the 4th, 6th and 10th are not minimum, but still be rated over 9.0.