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[Pat]

this puzzle requires "advanced" moves

1...2...3.4....5....6....4....53....2..7.8..1....91....6....4....5....7.3...1...2

[ play ]

22 cells given
(layout 202 of the Patterns Game)

Code: Select all


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



[pjb]

Code: Select all

1      5789   789    | 4689   2      45679  | 6789   689    3     
789    4      23     | 13689  678    3679   | 5      12     6789   
5789   23     6      | 1389   578    3579   | 12     4      789   
---------------------+----------------------+---------------------
46789  1789   14789  | 5      3      246    | 26789  2689   46789 
2      359    349    | 7      46     8      | 369    3569   1     
45678  3578   3478   | 246    9      1      | 23678  23568  45678 
---------------------+----------------------+---------------------
789    6      12     | 2389   578    23579  | 4      13     589   
489    12     5      | 234689 468    23469  | 13     7      689   
3      789    4789   | 4689   1      45679  | 689    5689   2


An SK-loop:
(57=89)r23c1 - (89=47)r78c1 - (47=89)r9c23 - (89=56)r9c78 - (56=89)r78c9 - (89=67)r23c9 - (67=89)r1c78 - (89=57)r1c23 - (57)r23c1: loop
Eliminations: r1c4 <> 89; r1c6 <> 9; r9c4 <> 89; r9c6 <> 9; r4c1 <> 89; r6c1 <> 8; r4c9 <> 89; r6c9 <> 8;

After these, a naked pair of 46s, a naked triple of 467s, and a sashimi Xwing of 4s to finish.

Phil

[ArkieTech]

After 4 quads 2 jelly's and a swordfish I find a pair and single! Nice puzzle Pat.

Would have continued but I had to go to church. ..and I am exhausted.

After church, refreshed and renewed I continued... a triple and a sashimi x-wing finished it out.

Pat, please don't tell me you solved this without pencil marks.

[pjb]

A very fishy puzzle indeed! It also has a rank zero 'multifish' pattern of 12389:

20 Truths = {12389R2, 12389R3, 12389R7, 12389R8}
20 Links = {89c1, 8c5, 239c6, 89c9, 2n348, 3n247, 7n348, 8n247}
12 Eliminations: r2c4<>6, r8c4<>46, r1c6<>9, r4c1<>89, r4c6<>2, r4c9<>89, r6c1<>8, r6c9<>89

After this, there is a naked triple of 467, a naked quad of 1389, and a sashimi X-wing of 4s to finish.

Phil

[Luke]

Code: Select all

1      5789   789    | 4689   2      45679  | 6789   689    3     
789    4      23     | 13689  678    3679   | 5      12     6789   
5789   23     6      | 1389   578    3579   | 12     4      789   
---------------------+----------------------+---------------------
46789  1789   14789  | 5      3      246    | 26789  2689   46789 
2      359    349    | 7      46     8      | 369    3569   1     
45678  3578   3478   | 246    9      1      | 23678  23568  45678 
---------------------+----------------------+---------------------
789    6      12     | 2389   578    23579  | 4      13     589   
489    12     5      | 234689 468    23469  | 13     7      689   
3      789    4789   | 4689   1      45679  | 689    5689   2


An SK-loop:
(57=89)r23c1 - (89=47)r78c1 - (47=89)r9c23 - (89=56)r9c78 - (56=89)r78c9 - (89=67)r23c9 - (67=89)r1c78 - (89=57)r1c23 - (57)r23c1: loop
Eliminations: r1c4 <> 89; r1c6 <> 9; r9c4 <> 89; r9c6 <> 9; r4c1 <> 89; r6c1 <> 8; r4c9 <> 89; r6c9 <> 8;

Tres cool

[Pat]

• 4 "hidden" pairs
• 2 Jellyfish
• c4 "naked" pair
  — finally, one cell solved (r6c4)
  
  
• r4 "naked" triple
• (7) Swordfish
• c6 "naked" triple
• (6) X-wing [ "sashimi" not needed ]

Pat, please don't tell me you solved this without pencil marks

actually i did —
but i'm stubborn;

also, i had this advantage:
i knew it could be solved by
"basic" moves + X-wing,Swordfish,Jellyfish
(puzzle qualifies as "superior plus"
and has now been re-posted there)

suppose the puzzles are filtered
and you know you will only need
"basic" moves + X-wing,Swordfish,Jellyfish
— in that case, looking for fish may be best

[DonM]

Code: Select all

1      5789   789    | 4689   2      45679  | 6789   689    3     
789    4      23     | 13689  678    3679   | 5      12     6789   
5789   23     6      | 1389   578    3579   | 12     4      789   
---------------------+----------------------+---------------------
46789  1789   14789  | 5      3      246    | 26789  2689   46789 
2      359    349    | 7      46     8      | 369    3569   1     
45678  3578   3478   | 246    9      1      | 23678  23568  45678 
---------------------+----------------------+---------------------
789    6      12     | 2389   578    23579  | 4      13     589   
489    12     5      | 234689 468    23469  | 13     7      689   
3      789    4789   | 4689   1      45679  | 689    5689   2


An SK-loop:
(57=89)r23c1 - (89=47)r78c1 - (47=89)r9c23 - (89=56)r9c78 - (56=89)r78c9 - (89=67)r23c9 - (67=89)r1c78 - (89=57)r1c23 - (57)r23c1: loop
Eliminations: r1c4 <> 89; r1c6 <> 9; r9c4 <> 89; r9c6 <> 9; r4c1 <> 89; r6c1 <> 8; r4c9 <> 89; r6c9 <> 8;

After these, a naked pair of 46s, a naked triple of 467s, and a sashimi Xwing of 4s to finish.

Phil

Is your solver programmed to find sk loops?

[pjb]

DonM wrote:

Is your solver programmed to find sk loops?

Yes. I've also been playing with variant SK loops and almost SK loops to extend the scope. With this puzzle, the 4 symmetrical naked pairs in boxes 1,3,7,9 stood out like a sore tooth, and made me suspect an SK loop was present. Once suspected, it was easy to spot without calling on the solver.

Phil

[DonM]

DonM wrote:

Is your solver programmed to find sk loops?

Yes. I've also been playing with variant SK loops and almost SK loops to extend the scope. With this puzzle, the 4 symmetrical naked pairs in boxes 1,3,7,9 stood out like a sore tooth, and made me suspect an SK loop was present. Once suspected, it was easy to spot without calling on the solver.

Phil

Well then, good eye!

[7b53]

Code: Select all

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

I didn't solve this, Pat ;
if one can spot the jellyfish, most likely it can be solved without PMs.

slightly different path,
first solved cell ... r5c5=4 (sashimi-x)
4 hidden pairs=>
2 jellyfish of {8,9}=>
naked pair of {4,6} column 4

surprisingly is all singles.