The New Sudoku Players' Forum

[Havard]

Hi.

I thought I would start a new thread on this one.

The idea is to take this puzzle:

Code: Select all

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


Made by JPF, suggested by Wapati, and turn it into 17's.

I will be posting the progress here, so you all can follow the procedure.

First step is to create more 19's. When going down in size, you will need quite a few 19's per 18 that is created.

I start by doing 1-off, 1-on on this 19, this produces:

Code: Select all

..1...2....3.4.5......6.......431...4.......62.......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6........31...4.......62.....4.7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........62.......7.9.8.2....6.....4..7.....1.

The repeating the 1-off, 1-on on this list again gives us:

Code: Select all

..1...2....3.4.5......6.......431...4.......62.......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6........31...4.......62.....4.7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........62.......7.9.8.2....6.....4..7.....1.
.51...2....3.4.5......6........31...4.......62.....4.7...8.2....6........7.....1.
..1..82....3...5......6.......431...........625......7...8.2....6.....4..7.....1.
..1..92....3...5......6.......431...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6........31...........625......7...8.2....6.....4..7.....15
..1...2....3.4.5.6....6.......431............25......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........6.25......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...2.......6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...8.......6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........6.5......7...8.2....6.....45.7.....1.
......2....3.4.5......6.......431...........628......7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......451...........62.......7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431......5....6........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431......9....6........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........86........7.9.8.2....6.....4..7.....1.

and doing it for a third time gives us:

Code: Select all

..1...2....3.4.5......6.......431...4.......62.......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6........31...4.......62.....4.7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........62.......7.9.8.2....6.....4..7.....1.
.51...2....3.4.5......6........31...4.......62.....4.7...8.2....6........7.....1.
..1..82....3...5......6.......431...........625......7...8.2....6.....4..7.....1.
..1..92....3...5......6.......431...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6........31...........625......7...8.2....6.....4..7.....15
..1...2....3.4.5.6....6.......431............25......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........6.25......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...2.......6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...8.......6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...........6.5......7...8.2....6.....45.7.....1.
......2....3.4.5......6.......431...........628......7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......451...........62.......7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431......5....6........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431......9....6........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........86........7.9.8.2....6.....4..7.....1.
.51...2......4.5......6........31...4.......62.....4.7...8.2...36........7.....1.
.51...2....3.4........6........31...4.......62.....4.7...8.2....6......8.7.....1.
.51...2....3.4.5......6........51...4.......62.....4.7...8.2....6........7.....1.
.51...2....3.4.5......6.........1...4.......62.....4.7...8.2....6........7...9.1.
..4..82....3...5......6.......431...........625......7...8.2....6.....4..7.....1.
..1..82....3...5......6.......431...8.......6.5......7...8.2....6.....4..7.....1.
..1..82....3...5......6.......431...........625......7...8.5....6.....4..7.....1.
..1..92....3...5......6......4.31...........625......7...8.2....6.....4..7.....1.
..1..92....3...5......6.......431...........625......7...8.2...6......4..7.....1.
..1..92....3...5...8..6.......431...........625......7...8.2....6........7.....1.
..14..2....3...5......6......4.31...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......7......4.31...........625......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31..........6.25......7...8.2....6.....4..7.....1.
..1.5.2....3.4.5......6......4.31...........6.5......7...8.2....6.....4..7.....1.
..1..82....3.4.5......6......4.31...........6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5.8....6......4.31...........6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5..8...6......4.31...........6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6...8..4.31...........6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.....84.31...........6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31.8.........6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31.......2...6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31........5..6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31..........86.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31...........6.5..8...7...8.2....6.....4..7.....1.
..1...2....3.4.5......6......4.31...........6.5......7...8.2....62....4..7.....1.
..1...2....3.4.5......6......4.31...........6.5......7...8.2....6.....48.7.....1.
..1...2....3.4.5......6......4.31...........6.5......7...8.2....6.....4..78....1.
..1...2....3.4.5......6......4.31...........6.5......7...8.2....6.....4..7.....18
..1...2.8..3.4.5......6......4.31...........62.......7...8.2....6.....4..7.....1.
..1...2....3.4.5......7........31...........625......7...8.2....6.....4..7.....15
..1...2....3.4.5......6........31...........625......7...8.2...6......4..7.....15
..1...2....3.4.5......6........31...........625......7...8.2....6.....4.7......15
..1...2....3.4.5......6........31...........625......7...8.2....6.....4..7.....35
..15..2....3...5.6....6.......431............25......7...8.2....6.....4..7.....1.
..19..2....3...5.6....6.......431............25......7...8.2....6.....4..7.....1.
..1..52....3...5.6....6.......431............25......7...8.2....6.....4..7.....1.
..1...2....3..75.6....6.......431............25......7...8.2....6.....4..7.....1.
..1...2....3...5.6....6.......431............25......7...8.2....6.3...4..7.....1.
..1...2....3...5.6....6.......431............25......7...8.2....6..5..4..7.....1.
..1...2....3...5.6....6.......431............25......7...8.2....6.....4..7..5..1.
..1...2....3...5.6....6.......431............25......7...8.2....6.....4..7...4.1.
..1...2....3...5.6....6.......431............25......7...8.2....6.....4..7...5.1.
..1...2....3.4...6....6.......431............25......7...8.2.5..6.....4..7.....1.
..1...2....3.4.5.6............431............25..6...7...8.2....6.....4..7.....1.
..1...2....3.4.5.6....6.......4.1.9..........25......7...8.2....6.....4..7.....1.
..1...2....3.4.5.6....6.......439............25......7...8.2....6.....4..7.....1.
..1...2....3.4.5.6....6.......431...2.........5......7...8.2....6.....4..7.....1.
..1...2....3.4.5.6....6.......431............25.....7....8.2....6.....4..7.....1.
..1...2....3.4.5.6....6.......431............25......7...8.5....6.....4..7.....1.
..1...2....3.4.5.6....6.......431............25......7...8.2....6.....8..7.....1.
..1...2....3.4.5......6.......4.1......9...6.25......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......4.1........9.6.25......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...2......6..5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........6.85......7...8.2....6.....4..7.....1.
..1...2.7..3.4.5......6.......431..........6.25..........8.2....6.....4..7.....1.
..1...2....3.4.5.7....6.......431..........6.25..........8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........6.25......7...8.5....6.....4..7.....1.
..1...2.8..3.4.5......6.......431..........6.25......7...8.2....6........7.....1.
..1...2....3.4.5......6.......431..........6.25......7...8.2....6.....4.7......1.
..19..2....3...5......6.......431...2.......6.5......7...8.2....6.....4..7.....1.
..1...2....3...5......6.......431...2.......6.5......7...8.2....6..5..4..7.....1.
..1...28...3.4.5......6.......43....2.......6.5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...2.....6...5......7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...2.......6.5......7...8.2..........4.67.....1.
..1...8....3.4.5......6.......431...8.......6.5......7...8.2....6.....4..7.....1.
..1...2....3...5......6.......431...8.......6.5......7...8.2....6.....4..7...9.1.
..1...2....3.4.5......6...8...431...8.......6........7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...8......96........7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...8.......6........7.5.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...8.......6.5......7...8.2.3..6.....4..7.......
..19..2....3...5......6.......431...........6.5......7...8.2....6.....45.7.....1.
8.1...2....3.4.5......6.......43............6.5......7...8.2....6.....45.7.....1.
..1...2....3.4.5......6.......431....2......6........7...8.2....6.....45.7.....1.
..1...2....3.4.5......6.......431...........6..5.....7...8.2....6.....45.7.....1.
..1...2....3.4.5......6...8...431...........6.5......7...8.2....6.....45.7.......
..1...2....3.4.5......6.......431...........6.5......7...8.2....6.....45.7.....3.
......2....1.4.5......6.......431...........628......7.9.8.2....6.....4..7.....1.
......2....3.4........6.7.....431...........628......7.9.8.2....6.....4..7.....1.
......2....3.4.5......6......5.31...........628......7.9.8.2....6.....4..7.....1.
......2....3.4.5......6.......435...........628......7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......451...2.......6........7.9.8.2....6.....4..7.....1.
..1...2....3.4.9......6.......431......5....6........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431......5....6........7.5.8.2....6.....4..7.....1.
..1...2..2...4.5......6.......431..........86........7.9.8.2....6.....4..7.....1.
..1...2....2.4.5......6.......431..........86........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......435..........86........7.9.8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431...5......86........7...8.2....6.....4..7.....1.
..1...2....3.4.5......6.......431..........86........7.9.8......6.....4..7...2.1.


107 19's, all closely related to the first one.

Now let's look for 18s!

Havard

[Havard]

the search for 18's in the list of 107 19's gave us these to start off with:
(doing a 2-off, 1-on on the 19's to make 18's)

Code: Select all

8.14..2....3...5......6......4..1...........6.5......7...8.2....6.....4..7.....1.
..19..2....3...5.6............431............25......7...8.2...76.....4........1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.....4..7.....1.
..1...2....3...5......6.......431...2.....8.6........7...8.2....6..5.....7.....1.

To make the base for expanding the 18's a bit bigger I do a 2-off, 2-on search on these ones, with this result:

Code: Select all

8.14..2....3...5......6......4..1...........6.5......7...8.2....6.....4..7.....1.
8.94..2....3..........6......4..1...........6.5......7...8.2.3..6.....4..7.....1.
8.14..2....3..........6......4..1...........6.5......7...8.2.1..6.....4..75......
8.14..2....3...5......6......4............1.6.5......7...8.2....6.....4..7.3.....
8.14..2....3...5......6......4............9.6.5......7...8.2....6.....4..7.3.....
8.14..2....3...5......6......4..1...........6....5...7...8.2....6........7.....19
8.14..2....3...5......6......4..1...........6......9.75..8.2....6.....4..7.......
..19..2....3...5.6............431............25......7...8.2...76.....4........1.
..49..2....3...5.6............431............25......7...8.2...76.....4........1.
..19..2....3...5.6............431............25......7...8.5...76.....4........1.
..49..2....3...5.6............431............25......7...8.5...76.....4........1.
..1...2.....9..5.6............431............25......7...8.2...76.....4...3....1.
..1...2......7.5.63...........431............25......7...8.2...76.....4........1.
..1...2.......75.63...........431............25......7...8.2...76.....4........1.
..19..2....3.....5............431............25......7...8.2...76.....4........16
..19..2.4..3.....6............431............25......7...8.2.5.76..............1.
..19..2....3...5..........6...431............25......7...85....76.....4........1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.....4..7.....1.
..1...2........5.6..3.6........41.9..........25......7...8.2....6.....4..7.....1.
..1...2........5.6....6........41.9..........25......7...8.2....63....4..7.....1.
..9...2........5.6..1.6........41.9..........25......7...8.2....6.....4..7.....1.
..1...2....3.....6....6.5......41.9..........25......7...8.2....6.....4..7.....1.
..1.....2......5.6..9.6........41.9..........25......7...8.2....6.....4..7.....1.
..1..42..........6....6.5......41.9..........25......7...8.2....6.....4..7.....1.
..1...2........5.69...6........41.9..........25......73....2....6.....4..7.....1.
..1...2.....3..5.6....6........41.9..........25......79..8......6.....4..7.....1.
..1...2........5.6....6.3......41.9..........25......7...8.2....6.5......7.....1.
..1...2........5.6....6........41.9.....5....25......7...8.2....64.......7.....1.
..1...2....9...5.6....6........41.9..........25......7...8.2....6.....4.7......1.
..1...2........5.6....69.......41.9..........25......7...8.2....6.....4...7....1.
..1...2....3...5.7....6........41.9..........25......6...8.2....6.....4..7.....1.
..1...2....3...5.6....7........41.9..........25......7...8.2..........4.67.....1.
..1...2....38..5.6....6.........1.9......4...25......7.....2....6.....4..7.....1.
..1...2....3...5.6....6........41.9..........25......7...8.2..........4.76.....1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.5.....7......1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.....3.7......1.
..1...2....3...5......6.......431...2.....8.6........7...8.2....6..5.....7.....1.
..1.......93...5......6.......431...2.....8.6........7...8.2...6...5.....7.....1.
..1...2..4.3...5......6......4.31.........8.6........7...8.2....6..5.....7.....1.
..1...2....3...5......6..4....4.1...2.......6........7...8.2....6..5.....79....1.
..1...2....3...5...4..6.......4.1...2.....8.6........7...8.2...6...5.....7.....1.


And then I go on to do 1-off, 1-on on these list, again and again!

Code: Select all

8.14..2....3...5......6......4..1...........6.5......7...8.2....6.....4..7.....1.
8.94..2....3..........6......4..1...........6.5......7...8.2.3..6.....4..7.....1.
8.94..2....3..........6......4..1...........6.5......7...8.2.3..6.....4.7......1.
8.14..2....3..........6......4..1...........6.5......7...8.2.1..6.....4..75......
9.14..2....3..........6......4..1...........6.5......7...8.2.1..6.....4..75......
8.14..2....3..........6......4..1...........6.5......7...8.2.1..6....4...75......
8.14..2....3...5......6......4............1.6.5......7...8.2....6.....4..7.3.....
8.94..2....3...5......6......4............1.6.5......7...8.2....6.....4..7.3.....
8.14..2....3...5......6......4..1...........6....5...7...8.2....6........7.....19
8.14..2....3...5......6......41.............6....5...7...8.2....6........7.....19
8.14..2....3...5......6......4..1...........6......9.75..8.2....6.....4..7.......
8.1...2....3...5......6......4..1.......3...6......9.75..8.2....6.....4..7.......
8.1...2....3...5......6......4..1...........6.....39.75..8.2....6.....4..7.......
8.14..3....3...5......6......4..1...........6......9.75..8.2....6.....4..7.......
8.14..2....3...5......6......4..8...........6......9.75..8.2....6.....4..7.......
8.14..2....3...5......6......4..1..........76......9..5..8.2....6.....4..7.......
..19..2....3...5.6............431............25......7...8.2...76.....4........1.
..49..2....3...5.6............431............25......7...8.2...76.....4........1.
..19..2....3...5.6............431............25......7...8.5...76.....4........1.
..49..2....3...5.6............431............25......7...8.5...76.....4........1.
..1...2.....9..5.6............431............25......7...8.2...76.....4...3....1.
..1...2......7.5.63...........431............25......7...8.2...76.....4........1.
..1...2.......75.63...........431............25......7...8.2...76.....4........1.
..1...2......7.5.63...........431............25......7.....2...76.....4....8...1.
..1...2......7.5.63...........431............25......7...8.2....63....4........1.
..1...2......7.5.63...........431............25......7...8.2....67....4........1.
..1..62.......75.63...........431............25......7...8.2....6.....4........1.
..19..2....3.....5............431............25......7...8.2...76.....4........16
..19..2....3.....5............431............25..8...7.....2...76.....4........16
..19..2....3.....5............431............25......7...8.2....6.....4.7......16
..19..2.4..3.....6............431............25......7...8.2.5.76..............1.
..19..2....3...5..........6...431............25......7...85....76.....4........1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.....4..7.....1.
..1...2........5.6..3.6........41.9..........25......7...8.2....6.....4..7.....1.
..1...2........5.6....6........41.9..........25......7...8.2....63....4..7.....1.
..1...2....3.....6....6.5......41.9..........25......7...8.2....6.....4..7.....1.
..9...2........5.6..1.6........41.9..........25......7...8.2....6.....4..7.....1.
..9...2........5.6..1.6........41.9..5.......2.......7...8.2....6.....4..7.....1.
..1..42..........6....6.5......41.9..........25......7...8.2....6.....4..7.....1.
..1.....2......5.6..9.6........41.9..........25......7...8.2....6.....4..7.....1.
..1.....2......5.6..9.6........41.9..........25......7...8.2....6.....4.....3..1.
..1..42..........6....6.5......4..9......1...25......7...8.2....6.....4..7.....1.
..1...2........5.69...6........41.9..........25......73....2....6.....4..7.....1.
..1...2.....3..5.6....6........41.9..........25......79..8......6.....4..7.....1.
..1.........3..5.6....6........41.9..........25......79..8...2..6.....4..7.....1.
..1...2........5.6....6.3......41.9..........25......7...8.2....6.5......7.....1.
..1...2........5.6....6........41.9.....5....25......7...8.2....64.......7.....1.
..1...2....9...5.6....6........41.9..........25......7...8.2....6.....4.7......1.
..1...2........5.6....69.......41.9..........25......7...8.2....6.....4...7....1.
..1...2....3...5.7....6........41.9..........25......6...8.2....6.....4..7.....1.
..1...2....3.....7....6.5......41.9..........25......6...8.2....6.....4..7.....1.
..1...2....3.....7....6........41.9..........25......6...8.25...6.....4..7.....1.
..1...2....3...5.6....7........41.9..........25......7...8.2..........4.67.....1.
..1...2........5.6.9..7........41.9..........25......7...8.2..........4.67.....1.
..1...2....3.....6....7.5......41.9..........25......7...8.2..........4.67.....1.
..1...2....3.....6....7........41.9..........25......7...8.25.........4.67.....1.
..1...2....3...5.6....7........41.9..........25......7...8.2..........3.67.....1.
..1...2....38..5.6....6.........1.9......4...25......7.....2....6.....4..7.....1.
..1...23....8..5.6....6.........1.9......4...25......7.....2....6.....4..7.....1.
..1...2.....8..576....6.........1.9......4...25......7.....2....6.....4..7.....1.
..1...2.....8..5.6..7.6.........1.9......4...25......7.....2....6.....4..7.....1.
..1...2....3...5.6....6........41.9..........25......7...8.2..........4.76.....1.
..1...2....3.....6....6.5......41.9..........25......7...8.2..........4.76.....1.
..1...2....3...5.6....6........41.9..........25......7...8.2..........3.76.....1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.5.....7......1.
..1...2....3...5.6....6........41.9..........25......7...8.2....6.....3.7......1.
..1...2....3...5......6.......431...2.....8.6........7...8.2....6..5.....7.....1.
..1.......93...5......6.......431...2.....8.6........7...8.2...6...5.....7.....1.
..1.......94...5......6.......431...2.....8.6........7...8.2...6...5.....7.....1.
..1.......93...5......6......9.31...2.....8.6........7...8.2...6...5.....7.....1.
..1.......93...5......6.......4.1...2.....896........7...8.2...6...5.....7.....1.
..1...2..4.3...5......6......4.31.........8.6........7...8.2....6..5.....7.....1.
..1...2..4.3...9......6......4.31.........8.6........7...8.2....6..5.....7.....1.
..1...2..4.3...5......6......4..1......5..8.6........7...8.2....6..5.....7.....1.
..1...2..4.3...5......6......4..1.........8.6.......57...8.2....6..5.....7.....1.
..1...2..4.3...5......6......4.31...........6......8.7...8.2....6..5.....7.....1.
..1.5.2..4.3...5......6......4.31.........8.6........7...8.2....6........7.....1.
..1...2..4.3...5......6......4.31.........8.6........7...8.2....6.5......7.....1.
..1...2....3...5......6..4....4.1...2.......6........7...8.2....6..5.....79....1.
..1...2....3...5......7..4....4.1...2.......6........7...8.2....6..5.....79....1.
..1...2....3...5......6..4....4.1...........62.......7...8.2....6..5.....79....1.
..1...2....3...5......6..4....4.1...2.......6........7.....28...6..5.....79....1.
..1...2....3...5...4..6.......4.1...2.....8.6........7...8.2...6...5.....7.....1.
..1...2....3...5...4..6.......4.1...2.....8.6........7...8.2...6.........74....1.


until I reach a total of 3460 18 sudoku.

These are now being searched for a 17!

Havard

[Havard]

by doing a 2-off, 1-on on those 3460 18's, these 17's popped out:

Code: Select all

2.1........3.........96......4..1...........6.5......7...8.2.1..6.....49.7.......
5.19.......3..........6......4.....9......2.6........7...8.2.3..6.....4..7.5.....
9.14.............5....6.8.....9.............6.5..3...7...1.2.9..6.....4..7.......
..18..2....3..........6......4..1........9..6......8.7.7...2...96..5...........1.
9.1...3...............7......34.1...........6..8...5.7.....28...6.......47.9.....
..1..32............4..7......89.1...........6..4...5.7.....2.9..6..5.....7.......


and out of these, this one is new:

Code: Select all

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

it has been added to the Gordon database with the ID# 40156.

So that's it. The whole process took a bit more than one hour on my pentium 4, 2.0 Ghz. A few minutes to generate the 18's, and around an hour for the 2-off 1-on search. 1 out of 6 being new is a very high ratio, and I was surprised that any new ones came out of this. Maybe this is a good search to expand further, (make a lot more of the same 18's, and do another search) but I just wanted to demonstrate the technique I have been using to find 17's lately.

Havard

[JPF]

Thanks Havard and congratulations, again.
It's neat and your algorithm seems to be very efficient for finding new 17s.

My question is : what 19s (or whatever number of clues) are the best ones to start with ?
I don't think that symmetries, non diagonal boxes etc... in the starting puzzle are very usefull

JPF

[Havard]

thanks.

I have no idea what 19's are suited for this search... Have only done this operation a few times...
Any ideas, theories on the matter would be appreciated!

Havard

[tarek]

This is a very good idea Havard..........

I'm sure more will be on the way

tarek

[wapati]

thanks.

I have no idea what 19's are suited for this search... Have only done this operation a few times...
Any ideas, theories on the matter would be appreciated!

Havard

Is there information on whether minimal 18s are more productive?

One would think that minimals might be most likely to generate new 17s, if one were me!

[coloin]

I think Havard is generating minimal 18s....[a non minimal 18 is a 17 in disguise]........here is another one just published......

Code: Select all

+---+---+---+
|123|...|...|
|...|456|...|
|...|...|...|
+---+---+---+
|...|...|417|
|...|...|...|
|865|...|...|
+---+---+---+
|...|...|...|
|...|198|...|
|...|...|526|
+---+---+---+

Go Havard !

C

[gsf]

So that's it. The whole process took a bit more than one hour on my pentium 4, 2.0 Ghz. A few minutes to generate the 18's, and around an hour for the 2-off 1-on search. 1 out of 6 being new is a very high ratio, and I was surprised that any new ones came out of this. Maybe this is a good search to expand further, (make a lot more of the same 18's, and do another search) but I just wanted to demonstrate the technique I have been using to find 17's lately.

I'm trying to reproduce your sequence and am far more than 1hr
e.g., it takes ~27 min for me to get the first 4 18s @2Ghz
2-off on the 107 19s yields 16126 (possibly pseudo) puzzles (~1 sec)
1-on on those yields 4 18s but in that process 4372125 distinct possible 18s are checked
that took ~27min for a rate of ~2700(canonicalizations+solves)/sec/Ghz

I've got to be missing something simple in the 1-on code
how long did your (107 19s) => (4 18s) take?
can you describe any pruning/insights in that process?
thanks

[Havard]

I'm trying to reproduce your sequence and am far more than 1hr
e.g., it takes ~27 min for me to get the first 4 18s @2Ghz
2-off on the 107 19s yields 16126 (possibly pseudo) puzzles (~1 sec)
1-on on those yields 4 18s but in that process 4372125 distinct possible 18s are checked
that took ~27min for a rate of ~2700(canonicalizations+solves)/sec/Ghz

I've got to be missing something simple in the 1-on code
how long did your (107 19s) => (4 18s) take?
can you describe any pruning/insights in that process?
thanks

I have a process running at the moment, but when it is finished I will do a rerun with timing. (EDIT: it took 182 seconds.) 2 small things I can think of is that I make sure that the initial candidategrid of the 17-subgrid does not contain any illegal candidates before any backtracking starts, and a short and fast logical solver is used for pruning during the "trying all options"-stage.

Havard

[Havard]

I think Havard is generating minimal 18s....[a non minimal 18 is a 17 in disguise]........here is another one just published......

Code: Select all

+---+---+---+
|123|...|...|
|...|456|...|
|...|...|...|
+---+---+---+
|...|...|417|
|...|...|...|
|865|...|...|
+---+---+---+
|...|...|...|
|...|198|...|
|...|...|526|
+---+---+---+

Go Havard !

C

I put this one, and this one from Mauricio:

Code: Select all

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

together, made 18000 18's out of them, and these 17's came out:

Code: Select all

.........31.4.........9.6.2......7..4..3.......6...2.9..2.........8.1.3.7........
.........35.4...1.....9.6.2......7.....3.......6...2.9..2.........5.1.3.7........
........235.4..........86........7...4.3.......6...2.9..2.........5.1.3.7........
1.......2.3...5..........6.........1...3.8.....9...2.7..27........9.1.3..4.......
.........13.4.........7.6.2......9.......3.....6...2.7..2.........5.1.3.74.......
.1.....82.3.4.5.........6............8.3.......65..2....2.........9.1.3.5........
.1........3.4.9.........6.2..........5...3.....6...2.7..2.7.........1.3..4....9..
.....86.293.4....................5.....3.......6...2.7..2.........9.1.3.74.......
.....86.23..4......9.............5.....3.......6...2.7..2.........9.1.3.74.......
......6.2.3.4......9.........5..8......3....1..6...2....2.........91..3.74.......
.1...9....3.4...........6.2..........5...3.....6...2.7..2.7.........1.3..4....9..
.1........3.4.9.........8.2..........5...3.....6...2.7..2.7.........1.3..4....9..
19.....5..3..65.......2................358.....6...2.7..2.........9...3.7........
.......62.314.....9................9...3.......6...2.7..2..7......9.1.3..5.......
9.........3.4....8.....6..2............35......6...2.7..2..7......9...3..5......4
9.........3.4..........6..2......1.....35......6...2.7..2..7......9...3..5......4
9.........3.4........6...42...3.............9..6...2.7..2..7......9.1.3..5.......
9.......2.384...............8.3.............9..6...2.7..2..7......9.1.3..5.......
9.......2.3.4...6...........8.3.............9..6...2.7..2..7......9.1.3..5.......
.....86.239.4....................5.....3.......6...2.7..2.........9.1.3.74.......
.1...9....3.4...........8.2..........5...3.....6...2.7..2.7.........1.3..4....9..
.1........3...9..........42........6.5...3.....6...2.7..2.7.........1.3.7.....9..
.1........3.4.9...........2........6.5...3.....6...2.7..2.7.........1.3..8....9..
........2.3.4.5.......7.6.1..........9.3.4.....6.....7............9..83.7.2......
.......82.3.1.9...........6...5......9.3.8.....6...2.7..2.........9...3.7........
.9........3...........2.68.............358.....6...2.7..2.6.......9...3.7......4.
19.....8..3..6........2.9..............358.....6...2.7..2.........9...3.7........
...8...62.3.1.....9................9...3.......6...2.7..2..7......9.1.3..5.......
...8...62.3.4.....9................9...35......6...2.7..2..7......9...3..5.......
........2.3.4...6.9................9.4.3.......6...2.7..2..7......9.1.3..5.......
........2.3.4...8.9................9.4.3.......6...2.7..2..7......9.1.3..5.......
.......52.3.4.....9................9.8.3.......6...2.7..2..7......9.1.3..5.......
........2.3.4...6.9................9.8.3.......6...2.7..2..7......9.1.3..5.......
........2.3.4.8...9................9...38......6...2.7..2..7......91..3..5.......
........2.3.4...6.9................9...38......6...2.7..2..7......91..3..5.......
9.........3.4..........6.82............35......6...2.7..2..7......9...3..5......4
9.........3.4....1.....6..2....5.......3.......6...2.7..2..7......9...3..5......4
.9........3.4...........6.2............351.....6...2.7..2..7......9...3..5....4..
......8.253.4...........6..............3....9..5.8.2....2.........9.1.3.74.......
......8.293.4......1...................3.4.....6...2.7..2.7.......1...3..5....4..
......9.293.4......1...................3.4.....6...2.7..2.7.......1...3..5....4..
1.........3.4...9....2..6........7..2..3.......6...2.8.72...........1.3.........4
.........13.4.........8.6.2........7.4.3.......6...2.8..2.........9.1.3..7.......
....7....53.4...........6........7..9..3.......6...2.8..2.........9.1.3..7.....4.
....5....13.............6.2......7.....3.4.....6...2.9..2.9.......5.1.3..7.......
.........13.............6.2..4..75.....3.......6...2.4..2.4.......9.1.3..7.......
.........53.4..........86.2......7.....3.......6...2.9..2.7.......5...3.1.......4
1.........3.4.........7.6........7..8..3.......6...2.9..2.........5.1.3..7......4
.........53.4.........8.6.2......7.....3.......6...2.9..2..1......5...3..9......4
.........53.4...........6.2....8.1.....3.......6...2.9..2..9......5...3..8......4
.........53.4..........16.2......7.....3.......6...2.9..2.9.......5...3..8......4


It should be easy to tell which 17 belong to which 18!

Out of these, these three were new:

Code: Select all

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

Code: Select all

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

Code: Select all

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

I have entered the two last ones into the Gordon database (#ID 40573, 40574) but the first one I for some reason get a blank page when I try to enter it?

Havard

[Pat]

I have entered the two last ones into the Gordon database
(#40573- 40574)

but the first one I for some reason get a blank page when I try to enter it?

hi Havard,
i've submitted it in your name:

#40582

Code: Select all

.1.....82.3.4.5.........6............8.3.......65..2....2.........9.1.3.5........



it had to be entered with zeroes --

Code: Select all

010000082030405000000000600000000000080300000006500200002000000000901030500000000



~ Pat

[Havard]

hi Havard,
i've submitted it in your name:

#40582

Code: Select all

.1.....82.3.4.5.........6............8.3.......65..2....2.........9.1.3.5........



it had to be entered with zeroes --

Code: Select all

010000082030405000000000600000000000080300000006500200002000000000901030500000000



~ Pat

thanks Pat! Funny that all the others would enter without the zeroes...

Havard

[gsf]

I have a process running at the moment, but when it is finished I will do a rerun with timing. (EDIT: it took 182 seconds.) 2 small things I can think of is that I make sure that the initial candidategrid of the 17-subgrid does not contain any illegal candidates before any backtracking starts, and a short and fast logical solver is used for pruning during the "trying all options"-stage.

I'm an order of magnitude off
can you post the #candidategrids before the illegal candidate check
(this would be the 2-off of the 107 19's -- I get 16126)
and the #puzzles presented to the logical solver
(this would be the 1-on of the 16126 -- I get 4372125)
thanks

[gfroyle]

thanks Pat! Funny that all the others would enter without the zeroes...

Havard

They don't have to be entered with zeros...

The problem is likely to related to some issues here with the computer on which the database is stored; hopefully these are now resolved..

Gordon