The New Sudoku Players' Forum

by **coloin** » Wed Jun 27, 2012 8:30 pm

eleven wrote: How many 19's do you have so far ?

probably more than 200,000.
unfortunately i dont know how many individual patterns [19clues with 3 clues in column5] i have gone through.
i suppose i perform a successive --similar 2 with gridchecker until it fizzles out.
Taking a symmetrical 19 and doing a selective {-2} to give a symmetrical 17subpuzzle and then {+2] potentially gives new patterns, but this is slow.

C

by **Serg** » Thu Jun 28, 2012 8:06 am

Hi, coloin!
I confirm that your last pattern (#113) is new unique 18-clue sym. pattern. (Published puzzle is minimal.)
It turns out, that you discovered pattern beloning to new distribution, not observed earlier. (Sym. 18-clue patterns having empty box are rare, 4 such patterns are observed only.) Congratulations!

Moreover, this new distribution (011222334) is lowest in sym. 18-clue patterns distribution list. So, you expanded limits of known sym. 18-clue patterns! Well done!

Serg

by **coloin** » Mon Jul 09, 2012 2:13 pm

Code: Select all: +---+---+---+ |.1.|...|.2.| |.3.|...|.4.| |...|567|...| +---+---+---+ |..1|...|7..| |...|3.2|...| |...|.4.|...| +---+---+---+ |...|2.1|...| |..7|...|6..| |..5|...|8..| +---+---+---+ .1.....2..3.....4....567.....1...7.....3.2.......4.......2.1.....7...6....5...8.. # 114 coloin

There cant be many left to find now
C

by **Serg** » Tue Jul 10, 2012 9:30 pm

Hi, coloin!

coloin wrote:
Code: Select all
.1.....2..3.....4....567.....1...7.....3.2.......4.......2.1.....7...6....5...8.. # 114 coloin

I confirm that you've found new 18-clue vertically symmetric pattern. Congratulations!
Published puzzle is minimal.

I've decided to add "natural" view of your last puzzle.

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

Nice configuration! It resembles me a cat (or armchair). This is why I like sym. puzzles.

Serg

[Edited. I added "natural" representation of the puzzle #114.]

by **eleven** » Wed Jul 11, 2012 5:09 pm

Nice equivalent pattern, there are many pretty ones for this puzzle, e.g.

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

Congrats on another one, Coloin. This one has 9 known ones in {-5+5}.

coloin wrote:There cant be many left to find now

So your 19 collection does not grow much any longer?

Here's my update.
Posted:

Hidden Text: Show

Patterns sorted:

Hidden Text: Show

Puzzles:

Hidden Text: Show

by **coloin** » Mon Jul 23, 2012 4:39 pm

My 19 collection is still increasing ..... maybe half a million now.
Came back from holiday to this new one

Code: Select all: +---+---+---+ |...|.1.|...| |..2|...|3..| |.4.|...|.5.| +---+---+---+ |..6|...|7..| |...|8.9|...| |..9|...|2..| +---+---+---+ |.5.|.7.|.4.| |.8.|...|.9.| |1..|...|..5| +---+---+---+ ....1......2...3...4.....5...6...7.....8.9.....9...2...5..7..4..8.....9.1.......5 # 115 coloin

C

by **Serg** » Tue Jul 24, 2012 6:45 am

Hi, coloin!

coloin wrote:....1......2...3...4.....5...6...7.....8.9.....9...2...5..7..4..8.....9.1.......5 # 115 coloin

I confirm that you've found new 18-clue vertically symmetric pattern. Congratulations!
Published puzzle is minimal.

This is "natural" view of the puzzle:

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

Nice configuration! It resembles me russian church.
How many new sym. 18-clue patterns are you expecting to find else?

Serg

by **coloin** » Tue Jul 24, 2012 3:18 pm

Serg wrote:How many new sym. 18-clue patterns are you expecting to find else?

thinking about it .... depending on the number of clues in column 5 [2 or 4] the number of symmetric 19 patterns is x7 and x5 respectively the symmetric 18 patterns.
i dont think i have searched 19 patterns with only one clue in column 5.

i dont know how many of the 19 patterns i have gone through - i am still finding new 19 patterns - so it is impossible to know if there will still be new puzzles undiscovered.......

C

by **coloin** » Thu Aug 09, 2012 11:05 pm

Finally - another one - like no other !

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

Code: Select all: +---+---+---+ |1..|...|..2| |...|...|...| |...|345|...| +---+---+---+ |...|162|...| |...|...|...| |..3|...|4..| +---+---+---+ |.34|...|78.| |..5|...|3..| |...|6.1|...| +---+---+---+

Like all the recent additions it has 2 clues in c5

It looks like we have found all the puzzles of the previous 115 patterns.

6 clues in c5 would appear impossible - i have been unable to find 19 clue symmetrical puzzles with 7 clues in c5

No clues in c5 would also appear to be a no-no. I have been able to find 19 clue symmetrical puzzles with 1 clue in c5 - but as mentioned before there seems to be a requirement to always need this clue.

C

by **dobrichev** » Fri Aug 10, 2012 1:10 pm

Congratulations!

by **Serg** » Sat Aug 11, 2012 8:43 am

Hi, coloin!

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

I confirm that you've found new 18-clue vertically symmetric pattern. Congratulations!
Published puzzle is minimal. You found the first pattern having distribution 111123333 (distribution of clues over boxes)! Well done!
Moreover, this new pattern has a few unique properties. It is unique pattern having 4 boxes containing 1 clue. It is unique pattern having 4 boxes containing 3 clues. It is unique pattern having 1 box only containing 2 clues.

This is "natural" view of the puzzle:

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

Is it a jug?

Concerning possible number of clues in the central (c5) column.

Let me cite my own previous post in this thread (see my post), where I calculated possible number of symmetric 18-clue patterns (simple combinatorial calculations):

Code: Select all: Column c5 contains 0 clues: 94143280 patterns ( 4 %) Column c5 contains 2 clues: 1089372240 patterns (45 %) Column c5 contains 4 clues: 1051807680 patterns (44 %) Column c5 contains 6 clues: 163614528 patterns ( 7 %) Column c5 contains 8 clues: 3392928 patterns ( 0.1%)

I processed all 188268 "filtered out" patterns (filtered eleven's list of all possible essentially different sym. 18-clue patterns) and found such statistics:

Code: Select all: Column c5 contains 0 clues: 6937 patterns ( 4 %) Column c5 contains 2 clues: 81200 patterns (43 %) Column c5 contains 4 clues: 85353 patterns (45 %) Column c5 contains 6 clues: 14548 patterns ( 8 %) Column c5 contains 8 clues: 230 patterns ( 0.1%)

So, you can see, no variants of possible number of clues in the central column can be excluded yet.

This is statistics for observed patterns:

Code: Select all: Column c5 contains 0 clues: 0 patterns Column c5 contains 2 clues: 92 patterns (79 %) Column c5 contains 4 clues: 24 patterns (21 %) Column c5 contains 6 clues: 0 patterns Column c5 contains 8 clues: 0 patterns

As you can see, no patterns having 0, 6 or 8 clues in c5 column were observed yet.

Serg

[Edited: I shortened representation of number of patterns for different central column's configurations.]

by **coloin** » Sat Mar 02, 2013 12:18 am

Ive just had a look at this pattern .....and it doesnt appear to have valid puzzles

Code: Select all: +---+---+---+ |xxx|xxx|xxx| |...|.x.|...| |...|.x.|...| +---+---+---+ |xxx|.x.|xxx| |xxx|.x.|xxx| |xxx|.x.|xxx| +---+---+---+ |xxx|.x.|xxx| |xxx|.x.|xxx| |xxx|.x.|xxx| +---+---+---+

maybe more possible templates can be excluded - should we be able to prove it.....
C

by **dobrichev** » Sat Mar 02, 2013 4:09 am

Hi coloin,
You might collaborate with Serg who 20 days ago identified that pattern P36 has no valid puzzles.
Your pattern is a symmetric extension to this morph of the former

Code: Select all: +---+---+---+ |xxx|xxx|...| |...|.x.|...| |...|.x.|...| +---+---+---+ |xxx|.x.|xxx| |xxx|.x.|xxx| |xxx|.x.|xxx| +---+---+---+ |xxx|...|xxx| |xxx|...|xxx| |xxx|...|xxx| +---+---+---+

by **Serg** » Sat Mar 02, 2013 6:47 am

Hi, coloin!

coloin wrote:Ive just had a look at this pattern .....and it doesnt appear to have valid puzzles
Code: Select all
+---+---+---+ |xxx|xxx|xxx| |...|.x.|...| |...|.x.|...| +---+---+---+ |xxx|.x.|xxx| |xxx|.x.|xxx| |xxx|.x.|xxx| +---+---+---+ |xxx|.x.|xxx| |xxx|.x.|xxx| |xxx|.x.|xxx| +---+---+---+

It's very likely that this pattern has no valid puzzles, but right now I cannot check it because yesterday I encountered a problem in my searching program. I think I need several days to fix that problem. Then I'll check this pattern.

Serg

by **coloin** » Sat Mar 02, 2013 10:56 am

Hi, remind me again how you check a pattern ?

if a pattern is a potential puzzle
if all the empty spaces in a potential puzzle are pattern-i
Do you ?
generate all possible ED ways to fill the empty clue pattern [pattern-i]
generate a token grid completion for the pattern-i
show that each token pattern generated has > 1 sol ?

C

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