The New Sudoku Players' Forum

by **mith** » Wed Nov 05, 2025 10:56 pm

The 36 million is the 4+ million T&E(3) minimals + whatever was in my local copy of ph; there are relatively few trivalue oddagon puzzles in there.

The seed for the T&E(3) database was about 900 puzzles (I have them in a spreadsheet somewhere), 11.3+ SER, all found by me neighborhood searching starting from the ph2010 database (plus a relatively small number of other puzzles - I had been investigating 19c and had some of the 9.X puzzles with that diagonal pattern that was explored previously; anyway, the other puzzles likely didn't contribute much if anything to the search, and the T&E(3) puzzles almost certainly come from the trivalue oddagon puzzles already existing in ph2010).

Anyway, I still have all of that, I'll figure out some sensible way to make it available.

I ran a quick check against the threshold, since my threshold for keeping puzzles was lower (and when I started, I was also looking for high q2 and q1 puzzles so the focus wasn't entirely on skfr as a filter). Here's a summary of what's in there:

Code: Select all: clues SER>=10.5 skfr total 19 3 0 3 20 1527 145 1672 21 17692 21092 38784 22 119409 107384 226793 23 441375 353999 795374 24 778355 512746 1291101 25 597191 626208 1223399 26 901382 944165 1845547 27 415914 1183307 1599221 28 188980 1058993 1247973 29 101693 882608 984301 30 90912 607298 698210 31 88350 311076 399426 32 47914 74615 122529 33 6112 12248 18360 34 438 684 1122 35 330 1 331 36 4 0 4 total 10494150

(the "skfr" column is puzzles not meeting the SER threshold but with skfr>=10.5; probably many these are unrated by serate and may have skfr significantly higher than the threshold)

by **mith** » Wed Nov 05, 2025 10:59 pm

Also, what tool do you use for your canonical form? I had been using gsf's minlex (which is not true minlex, as discussed elsewhere), so that's what's in my databases, but I know you do a maxlex form instead.

by **champagne** » Thu Nov 06, 2025 8:01 am

mith wrote:The 36 million i..
Anyway, I still have all of that, I'll figure out some sensible way to make it available.

on my side, any text file of the puzzles is a good start
and 36 millions is less than some of my files out of the vicinity steps

by **champagne** » Thu Nov 06, 2025 8:36 am

mith wrote:Also, what tool do you use for your canonical form? I had been using gsf's minlex (which is not true minlex, as discussed elsewhere), so that's what's in my databases, but I know you do a maxlex form instead.

for several reasons, I changed my canonical morph.

as discussed in this thread
http://forum.enjoysudoku.com/high-density-files-for-solution-grids-and-18-clues-puzzles-t42669.html
I was looking for shorter morphs of the puzzles what was needed for huge darabases
I wanted something easy to use with the sort and other coreutil tools

On the other way, the solution grid appeared more and more as a key property of the puzzle.
I also had meantime implemented my virtual catalog giving an easy and quick {solution grid <=> rank}

All this together pushed me to the canonical morph described in this thread

Code: Select all: http://forum.enjoysudoku.com/proposal-for-a-canonical-puzzle-t45209.html

Depending on the use, a puzzle can now be shown as

The ED puzzle
a canonical name 25 bytes
a canonical name 19 bytes. This surely for local huge databases. My "known puzzles" database is now close to 300 million puzzles.

I use my own code but as explained in the last link, I have to build a DLL to replace my github release. This can be done in one or 2 days if it becomes urgent.

by **champagne** » Sun Nov 09, 2025 8:58 am

In the former PH database, without human error, a sudoku entering the base could not disappear.

Here, the situation is slightly different.

Once a solution grid has a hit, it will stay in the base, but within the solution grid, a new expanded puzzle can be subset of previous one.

Then the newly expanded sudoku will replace the old one
I have nearly finished my work and controls on the first addition to the dy_ph_th_2510 base.

Addition starts with 339 971 new minimal giving 42 933 new expanded.

At the end, 3948 puzzles of the old base are replaced by new ones.
If anybody is interested, I’ll give examples of such replacements

by **champagne** » Mon Nov 10, 2025 9:17 am

The update of the TH base is on my google drive

dy_ph_th_2511

As this was my first run of the update process, I only took new puzzles attached to an exixting solution grid of thr TH base, and yes, the count of solution grids is stable here.

Next step will be with all new puzzles, but I want before to see what is in solution grids having both TH and not TH puzzles.

by **champagne** » Tue Nov 11, 2025 8:41 am

first investigations in solution grids having currently puzzles in 'TH' and in 'noTH' show interesting points.

Part of the solution grids have in the 'noTH' side some degenerated TH as here first seen as 'TH' second as 'noTH'

Code: Select all: .2.4..7..........3.8...1..4....93.47.3714....94.5.731.39..14.75..197.43....3.5... 200719884 .2....7..........3.8.....6.....93.47.3714....94.5.731.39..14.75..197.43....3.5..1 200719884

and some with quite different cases

Code: Select all: ...45............2...1.2.....8...97.5.7....2669..2.8.5.629.8.578.52..69.97..6.2.8 607395124 O0WeWO5UgkkPJ5 109;134;2;0 ...4.67..........2...1.2.....8..597.5.7....2669..2.8.5.629.8.578.52..69.97....2.8 607395124 e1WeWS5UgkkP35 110;134;2;0 .....6.8...6.8.13..8.13...4.3........4...132....32...5.6...845.8...7....9..5..... 607395124 WYQQK0Y3ZYB290 26 105;0;0;0 .....6.8.4.6.8.13..8.13.....3........4...132....32...5.6...845.8...7....9..5..... 607395124 WgQQG0Y3ZYB290 26 106;0;0;0

many of theese puzzles could be of interest for players, but analysing all 454 cases will take time.

I'll post in the puzzle section some of solution grids cases

by **champagne** » Thu Nov 13, 2025 3:40 pm

slow process partly due to other tasks, but with a new recognition of the potential TH threat, I reduced significantly the count, mainly after recognition of degenerated TH threat.

The change is mainly in the 'assumed non TH' file where from 112296 puzzles I have now 9728 in 151 solution grids.

Likely, most of them have a 'non TH' threat as in the former example.

I have to see what I can do to avoid analyzis of each of theese 9728 puzzles (or 151 solution grids)

BTW, It is amazing to see such a small number of solution grids common to both files.

by **champagne** » Fri Nov 14, 2025 9:52 am

I first checked 42 puzzles of py TH file not recognized as having a TH threat in my code.

Most of them have a degenerated TH with one clue coming twice as in these 2 puzzles

Code: Select all: ....5678..571..2.686.....1521.56..78......6.2.86..715.....9..61..86.....69..3...7 |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 1349 234 12349 | 2349 5 6 | 7 8 349 | | 349 5 7 | 1 48 3489 | 2 349 6 | | 8 6 2349 | 23479 247 2349 | 349 1 5 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 2 1 349 | 5 6 349 | 349 7 8 | | 34579 347 3459 | 3489 148 13489 | 6 349 2 | | 349 8 6 | 2349 24 7 | 1 5 349 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 3457 2347 2345 | 2478 9 2458 | 3458 6 1 | | 13457 2347 8 | 6 1247 1245 | 3459 2349 349 | | 6 9 1245 | 248 3 12458 | 458 24 7 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|

Code: Select all: 1...567.9...1.9.36.9637........95....7.61.9.36.97.3.51..49.7..2..2..1.........3.. |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 1 2348 38 | 248 5 6 | 7 248 9 | | 24578 2458 578 | 1 248 9 | 2458 3 6 | | 2458 9 6 | 3 7 248 | 12458 1248 458 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 2348 12348 138 | 248 9 5 | 2468 24678 478 | | 2458 7 58 | 6 1 248 | 9 248 3 | | 6 248 9 | 7 248 3 | 248 5 1 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 358 13568 4 | 9 368 7 | 1568 168 2 | | 35789 3568 2 | 458 3468 1 | 4568 46789 4578 | | 5789 1568 1578 | 2458 2468 248 | 3 146789 4578 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|

No idea on my side of the possible nice path to solve them but somehow a surprise to see such a high rating for degenerated TH.

I am left with 8 puzzles in 6 solution grids seen as potentiel TH threat

Hidden Text: Show

here is the first one. I have doubts that this is a TH threat

Code: Select all: .23..67...56....2.7........2....7.5.....1.....3......73..9625715....3.6...28..934;452307986;cnG18KGGWvFKC7;29;110 123456789456789123798231645241397856867514392935628417384962571579143268612875934 |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 1489 2 3 | 145 4589 6 | 7 1489 589 | | 1489 5 6 | 1347 34789 1489 | 1348 2 389 | | 7 1489 1489 | 12345 234589 14589 | 13468 1489 35689 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 2 14689 1489 | 346 3489 7 | 13468 5 3689 | | 4689 46789 45789 | 23456 1 4589 | 23468 489 23689 | | 14689 3 14589 | 2456 24589 4589 | 12468 1489 7 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++| | 3 48 48 | 9 6 2 | 5 7 1 | | 5 179 179 | 147 47 3 | 28 6 28 | | 16 167 2 | 8 57 15 | 9 3 4 | |++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|++++++++++++++++++++++++++++++|

by **champagne** » Sun Nov 16, 2025 9:03 am

It is now established that I have some false TH in the TH base, likely in solution grids also in the "non TH" base.
for the solution grid 452307986, all current puzzles of the base seem to have the same exocet pattern with the same box 1 pattern.
Seen by a player, this is likely variants of the same paths (19 puzzles)

This also reduce by 1 the number, already very small, of solution grids having both TH and non TH high ratings.

Unhappily, I have no code to do the job and checking each solution grid is too long.
I have to give up waiting for a better analysis of the oddities.

I'll shift puzzles using my last version of the TH threat quick detection.

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