hard minimal 8 clues JSWX examples

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hard minimal 8 clues JSWX examples

Postby urhegyi » Sun Mar 07, 2021 11:45 pm

Yes, my first 8 clues example. It took some preparation but the result has a nice form too.
Code: Select all
#1/WX/B4,JS
...........3...2......4..............5.....9..............7......8...1...........
111111223441112233444222233444525533664555733665585777668888777668899977688999999

Can you give the SE rating for jigsawexplainer?(SiSeSuSo estimates this around 7.5)
Image
solution:
Hidden Text: Show
Code: Select all
761492583913586247582743916346918752257361498894235671635174829478629135129857364
111111557221115577222555577222353377662333877663343888664444888664499988644999999

hints found by SiSeSuSo:
Hidden Text: Show
Code: Select all
(UVW)XYZ-Wing  |
TUVWXYZ Wing (-4)W2r4 => (-4)r4c6 |
TUVWXYZ Wing (-7)W3r6 => (-7)r6c4
Last edited by urhegyi on Mon Mar 08, 2021 1:27 am, edited 1 time in total.
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Re: hard minimal 8 clues JSWX examples

Postby 1to9only » Mon Mar 08, 2021 12:48 am

Code: Select all
...........3...2......4..............5.....9..............7......8...1........... 111111223441112233444222233444525533664555733665585777668888777668899977688999999 JSWX  8 ED=7.2/2.9/2.6


Code: Select all
Difficulty rating: 7.2
This Windoku Jigsaw can be solved using the following logical methods:
70 x Hidden Single (1.0-1.5)
1 x Direct Claiming (1.9)
1 x Direct Hidden Pair (2.0)
1 x Direct Hidden Triplet (2.5)
23 x Cage Pointing (2.6)
36 x Claiming (2.8)
44 x Generalized Intersection (2.9)
4 x Hidden Pair (3.4)
1 x Forcing Chain (7.2)

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Re: hard minimal 8 clues JSWX examples

Postby 1to9only » Mon Mar 08, 2021 10:36 am

This JSWX layout is rather good at producing 8-clues:
Code: Select all
...............2...8.............7.........9..........6....4...........51........ JSWX ED=2.9/1.5/1.5
..........1..8..4....................5.....9....................7..2..3.......... JSWX ED=2.9/2.3/2.3
........3...5.......27.....................................48.......9...1........ JSWX ED=4.2/2.9/2.6
..........1.....4.............9.8...............2.5.............7.....3.......... JSWX ED=7.7/2.3/2.3
....9.....1.....4...................2.......8...................7.....3.....5.... JSWX ED=7.9/2.3/2.3
.....................7.3......9.8...............2.5......1.4..................... JSWX ED=8.1/8.1/2.9
....9........8.......7.3.................................1.4.......2........5.... JSWX ED=8.8/8.8/2.6
7..........3.......8....9...............................5....2.......1..........4 JSWX ED=8.9/8.9/2.6

111111223441112233444222233444525533664555733665585777668888777668899977688999999

Same solution grid: Show
Code: Select all
761492583913586247582743916346918752257361498894235671635174829478629135129857364
1to9only
 
Posts: 3448
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Re: hard minimal 8 clues JSWX examples

Postby urhegyi » Mon Mar 08, 2021 4:03 pm

It's most of all the number 6 which is missing. Except for your first example where the number three is missing. All the other numbers occur only once.
A few easy ones for the p&p solvers:
Code: Select all
.............8.................1.....57...49.....3.................2.............
..............................918.....7...4.....235..............................
7.......3....8.......................5.....9.......................2....1.......4
...........3...2.....................57...49.....................8...1...........
..........1.....4...................25.....98...................7.....3..........
...............................1....257...498....3...............................
..........1..8..4....................5.....9....................7..2..3..........
..1...5......8........................7...4........................2......9...3..
..............................9.8.....73.14.....2.5..............................

Code: Select all
111111223441112233444222233444525533664555733665585777668888777668899977688999999
urhegyi
 
Posts: 539
Joined: 13 April 2020

Re: hard minimal 8 clues JSWX examples

Postby urhegyi » Mon Mar 08, 2021 4:59 pm

I found one with each number occuring only once, so 9 clues. After removing the 6 at R5C5 I got a 8 clues JSWX and backtracking confirms 1 solution, so it's valid, but I have no idea of the rating. It must be hard.
Code: Select all
#1/WX/B4,JS
....9......3...2......4...................................7......8...1......5....
111111223441112233444222233444525533664555733665585777668888777668899977688999999
urhegyi
 
Posts: 539
Joined: 13 April 2020

Re: hard minimal 8 clues JSWX examples

Postby 1to9only » Tue Mar 09, 2021 12:17 am

Code: Select all
....9......3...2......4...................................7......8...1......5.... 111111223441112233444222233444525533664555733665585777668888777668899977688999999 JSWX  8 ED=9.1/9.1/2.6

urhegyi wrote:It's most of all the number 6 which is missing. Except for your first example where the number three is missing. All the other numbers occur only once.

This is probably just a coincidence! I've generated a few others where the 6 appears more often.

Code: Select all
........3...58.......7.....................................4.......29...1........ JSWX  8 ED=2.8/1.2/1.2
7.......3....8.......................5.....9.......................2....1.......4 JSWX  8 ED=2.8/2.3/2.3
..........1..8..4....................5.....9....................7..2..3.......... JSWX  8 ED=2.9/2.3/2.3
.......8....5............1.........................67..3..................9.....4 JSWX  8 ED=2.9/1.2/1.2
7....2....1.5.......................................................9.3....8....4 JSWX  8 ED=7.9/7.9/2.6
..1................8....9........7.............4........5....2................3.. JSWX  8 ED=8.1/8.1/2.6
....9..................3.........7..2.......8..4.........1..................5.... JSWX  8 ED=8.1/7.9/2.9
.........................1..4.....52.........89.....7..3......................... JSWX  8 ED=9.4/9.4/2.6

111111223441112233444222233444525533664555733665585777668888777668899977688999999

761492583913586247582743916346918752257361498894235671635174829478629135129857364

Code: Select all
....................5.4..8....9........3............6.......2.....7.............. JSWX  8 ED=8.8/7.7/2.6

111111223441112233444222233444525533664555733665585777668888777668899977688999999

678495123983127546125643987347982615516378492294531768731864259462759831859216374

Code: Select all
.............8........5...............1.................6....3.......4........92. JSWX  8 ED=2.9/1.9/1.9
.......8...............9....5.7...6...1..4.........2............................. JSWX  8 ED=7.1/1.7/1.7
....................31.97...............................64.58.................... JSWX  8 ED=10.0/10.0/2.8

111111223441112233444222233444525533664555733665585777668888777668899977688999999

124573689749682351683159742952748163361924578875396214296415837518237496437861925

Code: Select all
5............................9......1........3.......4..2.....67................. JSWX  8 ED=2.8/1.2/1.2
..................23.5.........4.................8.........7.16.................. JSWX  8 ED=7.7/2.8/2.8
....6.....4.....7...................1.......3...................5.....8.....2.... JSWX  8 ED=7.9/2.3/2.3
...7.........3.............8.........2.....6.........4.............1.........5... JSWX  8 ED=9.4/9.4/2.6

111111223441112233444222233444525533664555733665585777668888777668899977688999999

594761238648239175231578649879643521125894763367182954982457316753916482416325897

Some solution grids:

Code: Select all
723541896436892157891756432652439781187623549945168273268375914579214368314987625
678915324184327596325694187497182635536478912219543768743869251962751843851236479
284765913643918572915273648378641295592384761167539824839427156721856439456192387
162594387927386451384157926756928134431762598895473612673215849518649273249831765
824617539149532768537869142962143857758924613316795284295486371683271495471358926
842793651921654378653871924174925863368142795597316482416287539785439216239568147
854921736246735198731896245695243871178654923329167584567489312983512467412378659
762589134824136957139754826456823719917462583385941672641275398573698241298317465
938576142782143659146952783253784916619238574475621398321895467594367821867419235
759312648198645237642738195835194762267859314413286579586973421374521986921467853
672315984124987536985634127437128695596472318813549762749263851368751249251896473
243691875935874162871265934564937281182543697796158423458326719627419358319782546
861935472312476598475892316296317845548261937739524681624189753987653124153748269
968542713483716259712953486356481972279368541145237698637895124591624837824179365
159624873293875461874163295365297184481359627726438519538916742617542938942781356
925468137657132849138947652742653918819725463364871295271594386493286571586319724
239517684194683752687254193453198267762439518815746329346925871528371946971862435
364927815245816793817395246596241387783564921129758634658439172931672458472183569
651429738218735946739648215845213679976851423324987561587164392463592187192376854
958726341281345679346971285175284936639158724427613598513897462794562813862439157

111111223441112233444222233444525533664555733665585777668888777668899977688999999
1to9only
 
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Re: hard minimal 8 clues JSWX examples

Postby urhegyi » Thu Mar 11, 2021 1:59 pm

New layout with 8 clues example. Needs forcing nets. So SE 9+?
Code: Select all
#1/WX/B4,JS
.....................9.3............15.....74............6.8.....................
111155666211155566221157566222757566222777888334747888334749988334449998333449999

Image
analyze log:
Code: Select all
Eliminated candidates per Method and per Sudoku

Method   \  Sudoku |   SER |     1
                   |-------|------
Not counted elims  |     0 |    77
Naked Singles      |   0.1 |    36
Hidden Singles     |   0.2 |   123
Naked Pair    [2]  |     3 |     6
Naked Triple  [3]  |   3.6 |    16
Hidden Quad   [5]  |   5.4 |    12
Pointing/Claiming  |   2.8 |   156
Locked Singles[3]  |   2.9 |    16
Locked Singles[4]  |     3 |    26
Locked Singles[5]  |   3.1 |     5
XY-chain      [4]  |   4.6 |     1
XY-chain      [5]  |   5.1 |     1
Forcing Nets  [4]  |   9.4 |     4
Forcing Nets  [5]  |   9.5 |    10
                   |-------|------
Eliminated Cand's  |   489 |   489
Sum(SER * Cand's)  | 887.6 | 887.6

Initial Candidates :   489
Maximum SER rating :   9.5 <- Approach
Labour rating      : 887.6 <- Experimental rating
Guesses (BF/BT;FN) :   986
Time needed        : 00:00:08.920

solution:
Hidden Text: Show
Code: Select all
761492583832546791278953146946135827153829674529764318314678952485317269697281435
111155666211155566221157566222757566222777888334747888334749988334449998333449999
urhegyi
 
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Re: hard minimal 8 clues JSWX examples

Postby urhegyi » Fri Mar 12, 2021 3:47 pm

If the last posted example was to hard try thisone:
Code: Select all
#1/WX/B4,JS
..........3.....9...................18.....76...................4.....2..........
111155222111555222115554422336654442336666644833376644883377799888777999888779999

Image
solution:
Hidden Text: Show
Code: Select all
761492583538167492924583167497638251182954376653721849816275934349816725275349618
111155222111555222115554422336654442336666644833376644883377799888777999888779999
urhegyi
 
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Re: hard minimal 8 clues JSWX examples

Postby urhegyi » Sat Apr 03, 2021 4:14 pm

Most symmetrical 8 clues JSWX possible!
Image
Code: Select all
#1/WX/B4,JS
..............................219......7.4......638..............................
111133344221133344221133444222135544225555588665579888666779988667779988667779999
urhegyi
 
Posts: 539
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Re: hard minimal 8 clues JSWX examples

Postby Hajime » Sun Apr 04, 2021 5:25 am

urhegyi wrote:Most symmetrical 8 clues JSWX possible!
Code: Select all
#1/WX/B4,JS
..............................219......7.4......638..............................
111133344221133344221133444222135544225555588665579888666779988667779988667779999
very nice layout / puzzle :!:
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