The New Sudoku Players' Forum

by **Serg** » Sat Oct 12, 2013 7:46 pm

Hi, Afmob!

Afmob wrote:Here is (hopefully) another new symmetric 18 clue Sudoku:
Code: Select all
............123.....4...5..............456....1.....3....2.1.....6...4..4.5...7.8

Unfortunately this pattern is not new. It is isomorhic to pattern #116.

Serg

by **coloin** » Sat Oct 12, 2013 8:20 pm

It is actually a morph of the posted puzzle with pattern #116

Code: Select all: 1.......2............345......162..............3...4...34...78...5...3.....6.1... # 116

C

by **Afmob** » Sat Oct 12, 2013 8:25 pm

Sorry, my bad. I use eleven's post to check if I've found a new puzzle and coloin's one was not in this list.

by **Afmob** » Tue Dec 03, 2013 6:49 am

Here is a possible new symmetric 18 clue puzzle:

Code: Select all: ...........1...2...3..4..5............2...6..4...5...7...2.6.....68.13...7.....9.

Verification would be appreciated! BTW, I only got about 12,000 patterns left to examine, so we're close to the finish line.

by **eleven** » Tue Dec 03, 2013 2:57 pm

Congratulations! New puzzle and new pattern.

Here is the updated list of posted puzzles with a new pattern.

Hidden Text: Show

I also uploaded a picture with the known patterns there. The new one is nr 54.
You can see, that there is place for 2 more in the patterns you have left to examine

by **Serg** » Thu Dec 05, 2013 8:54 pm

Hi, Afmob!

Afmob wrote:Here is a possible new symmetric 18 clue puzzle:
Code: Select all
...........1...2...3..4..5............2...6..4...5...7...2.6.....68.13...7.....9.

Verification would be appreciated! BTW, I only got about 12,000 patterns left to examine, so we're close to the finish line.

I confirm you've found new 18-clue symmetric pattern (#118). Congratulations!
It looks like you can find 1-2 patterns else.

I updated my "distributions list" here.

Serg

by **Afmob** » Wed Dec 11, 2013 7:27 am

Here is another new(?) pattern and puzzle that is not in eleven's list.

Code: Select all: ...........1...2...3..4..5.....6.......178....9.....2...2...7....8...1..6...3...8

Patterns left to check: 7,480.

Edit: I just found another new pattern with one valid puzzle.

Code: Select all: ...........1...2...2..3..4.....5.......142...6.......7...6.4...8.......17...9...6

by **eleven** » Wed Dec 11, 2013 9:01 am

Congrats on pattern #119. Hope your cpu's will stand the last part too.

by **Pat** » Wed Dec 11, 2013 11:40 am

Afmob wrote:Here is another new(?) pattern and puzzle that is not in eleven's list.
Code: Select all
...........1...2...3..4..5.....6.......178....9.....2...2...7....8...1..6...3...8

Edit:
I just found another new pattern with one valid puzzle.
Code: Select all
...........1...2...2..3..4.....5.......142...6.......7...6.4...8.......17...9...6

editing an existing post
does not flag the Topic as having new material,
thus #120 may go un-noticed

by **Serg** » Wed Dec 11, 2013 9:11 pm

Hi, Afmob!

Afmob wrote:Here is another new(?) pattern and puzzle that is not in eleven's list.
Code: Select all
...........1...2...3..4..5.....6.......178....9.....2...2...7....8...1..6...3...8

Patterns left to check: 7,480.

Edit: I just found another new pattern with one valid puzzle.
Code: Select all
...........1...2...2..3..4.....5.......142...6.......7...6.4...8.......17...9...6

I confirm you've found 2 new symmetric 18-clue patterns (#119 and #120). Congratulations!
Both published puzzles are minimal.

I updated my "distributions list" here.

If pattern #120 really has 1 valid puzzle only, we can see the first known sudoku superpuzzle.

Code: Select all: . . . . . . . . . . . x . . . x . . . x . . x . . x . . . . . x . . . . . . . x x x . . . x . . . . . . . x . . . x . x . . . x . . . . . . . x x . . . x . . . x

It is necessary to find a puzzle having numbers (1-9) in the cells marked by "x" such that it has unique solution.The puzzle (superpuzzle solution) is unique up to pattern's isomorphic transformations and relabelling.

Serg

[Edited. I corrected statement about superpuzzle solution. Thanks to Afmob for his correction.]

by **Afmob** » Thu Dec 12, 2013 6:23 am

Serg wrote:The puzzle (superpuzzle solution) is unique up to relabelling.

I think you misunderstood me. When I said that this pattern has only one valid puzzle, I meant one valid puzzle with regards to pattern preserving transformations.

by **Serg** » Thu Dec 12, 2013 7:01 am

Hi, Afmob!

Afmob wrote:
Serg wrote:The puzzle (superpuzzle solution) is unique up to relabelling.

I think you misunderstood me. When I said that this pattern has only one valid puzzle, I meant one valid puzzle with regards to pattern preserving transformations.

You correction is right. More accurate statement: "The puzzle (superpuzzle solution) is unique up to pattern's isomorphic transformations and relabelling". Simply put, one should find, say, minimal lexicographic form of the valid puzzle (pattern's isomorphic transformations, not changing given pattern (i.e. pattern's automorphisms), and relabelling are permitted).

But I have some doubts. Does pattern #120 have 1 valid puzzle only (up to pattern's isomorphic transformations and relabelling) or 1 valid completion only (up to pattern's isomorphic transformations and relabelling)?

Serg

by **Afmob** » Thu Dec 12, 2013 7:52 am

I'm not sure what you are getting at. All valid puzzles of this pattern are ismorphic to the one I posted and the solutions (one unique solution per valid puzzle) are also isomorphic otherwise the valid puzzles wouldn't be essentially the same. But we need the pattern automorphisms, for instance if you only allow relabelling you would get more than one puzzle:

Code: Select all: ...........1...2...2..3..4.....5.......142...6.......7...6.4...8.......17...9...6 ...........1...2...2..3..4.....5.......241...6.......7...4.6...8.......17...9...6 ...........1...2...3..4..1.....5.......132...6.......7...3.7...2.......87...9...6 ...........1...2...3..4..1.....5.......231...6.......7...7.3...2.......87...9...6

I also think that it is confusing to call a puzzle a solution because normally a solution has no empty cells where as a puzzle can have empty cells.

Edit: Here is another new pattern:

Code: Select all: ...........1...2...3..4..5.....3......21.67..8.......1...2.3......7.1....5.....8.

by **Serg** » Thu Dec 12, 2013 12:14 pm

by **Afmob** » Thu Dec 12, 2013 2:22 pm

Your puzzle #120A is not valid.

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