## Search found 42 matches

Fri Jul 13, 2007 6:35 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 10 July 2007: Mutant Fish Eliminations
Replies: 5
Views: 7292
I believe the answer is yes for closed loop single-digit AICs. I don't know if that has actually been proven yet. I did cover that intersection concept in the constraint set section of that fish groups in AICs post. It hasn't been noticed by very many others working on fishy stuff though. Check out ...
Thu Jul 05, 2007 5:29 am
Forum: Daily Jigsaw Sudoku
Topic: Advanced jigsaw techniques and examples
Replies: 0
Views: 4050

### Advanced jigsaw techniques and examples

I have some advanced jigsaw techniques described in this post.
Wed Jul 04, 2007 7:19 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 5/13/07 Nightmare
Replies: 12
Views: 11638
Yes, Arcilla's trick converts fish into either hidden or naked sets. In Arcilla's representation, Almost Locked Sets and Almost Hidden Sets will correspond to finned fish, although the fin may not occupy the same box as any of the fish vertices (which is hard to see in Arcilla's representation) and ...
Wed Jul 04, 2007 7:02 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 5/20/07 Nightmare...7's grid
Replies: 6
Views: 7777
I am not sure what a hidden fish is. Unlike locked sets where a naked set is coupled with a hidden set, a fish group is always coupled with just another fish group. By stand-alone, I meant a fish deduction that could not be represented more simply, like with a hidden single or locked candidates dedu...
Fri Jun 22, 2007 6:46 am
Forum: Solving Techniques & Tips
Topic: AIC's for uniqueness arguments
Replies: 1
Views: 3219
I think any notation which shows the four corners somehow weakly inhibiting the completion of the deadly pattern best depicts what is going on. I like what you have written. There really is no standard though, and many people willl just use strong links between the extra candidates because that is t...
Thu Jun 21, 2007 7:30 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 5/20/07 Nightmare...7's grid
Replies: 6
Views: 7777
There is a trick. For there to be a stand-alone fish, you have to be able to have candidates seeing each other in a loop through the unsolved boxes. With this setup, the only cyclic path through any of the unsolved boxes would be b1-b2-b5-b6-b9-b7-b1.... Since the candidates in b1 and b7 cannot dire...
Thu Jun 14, 2007 2:20 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 5/13/07 Nightmare
Replies: 12
Views: 11638
Having additional ways to see easily overlooked reductions is no bad thing.
Sat Jun 02, 2007 5:13 pm
Forum: Daily Sudoku Nightmare & Archive
Topic: 1 June 2007 - "Almost" Swordfish
Replies: 7
Views: 8521
There is also a tutorial on Using Fish Groups and Constraint Groups in AICs

(note that box-line or box-box reductions are examples of simple constraint groups)
Sat Jun 02, 2007 4:53 pm
Forum: Daily Sudoku Nightmare & Archive
Topic: June 2, 2007 Nightmare - A BUG-Lite AIC
Replies: 0
Views: 4186

### June 2, 2007 Nightmare - A BUG-Lite AIC

*-----------* |4..|.3.|..1| |..5|...|7..| |71.|.9.|.85| |---+---+---| |...|...|...| |5..|8.6|..7| |19.|...|.52| |---+---+---| |...|.8.|...| |82.|3.1|.74| |.7.|...|.3.| *-----------* *--------------------------------------------------------------------* | 4 68 2689 |*57 3 *57 | 269 26 1 | | 269 36 5...
Fri Apr 27, 2007 8:34 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 22 April 2007, Grouped AIC's and Rings
Replies: 6
Views: 8348
AICs and Nice Loops are two different ways of envisioning the same reduction. Ultimately, one really cannot do any more than the other. Originally I tried to incorporate the AIC observations as a part of Nice Loops, but they were not accepted and so I presented AICs as an alternate and simplified wa...
Sun Apr 01, 2007 6:06 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 18 March 2007
Replies: 4
Views: 6240

### Re: 18 March 2007

An AIC which is (in effect) found by the Sudocue solver in a "Medusa Bridge" step is (4)r1c8 = (4-9)r4c8 = (9)r4c4 - (9)r1c4 = (9)r1c6 => r1c6 <> 4 Is there an equivalent ALS rule and/or Wing structure that reproduces this elimination? If it helps, this is basically a multi-digit version ...
Fri Mar 23, 2007 4:21 am
Forum: Solving Techniques & Tips
Topic: Almost Locked Candidates
Replies: 13
Views: 11190
You might find this interesting '/' does not contain X, Y,or Z .---------------------.-----------------.----------. | . . . | XYZ* XYZ* / | / / / | | XYZ XYZ . | . . . | . . . | | . . . | . . . | . . . | .---------------------.-----------------.----------. The ALC net loop above has the form &#...
Thu Mar 22, 2007 8:03 am
Forum: Solving Techniques & Tips
Topic: Almost Locked Candidates
Replies: 13
Views: 11190

### Re: Further Thoughts on ALC

/ does not contain X, Y,or Z .---------------------.-----------------.----------. | . . . | XYZ-+ XYZ-+ / | / / / | | XYZ XYZ *-XYZ | . . . | . . . | | *-XYZ *-XYZ *-XYZ | . . . | . . . | .---------------------.-----------------.----------. I couldn't really come up with anything using AIC's to gen...
Tue Mar 20, 2007 4:02 pm
Forum: Solving Techniques & Tips
Topic: Almost Locked Candidates
Replies: 13
Views: 11190
Nice deduction and presentation of the connection between the two concepts.
Sat Mar 17, 2007 7:25 am
Forum: Daily Sudoku Nightmare & Archive
Topic: 12/16/06 Nightmare - Revisited
Replies: 2
Views: 5238

### Re: 12/16/06 Nightmare - Revisited

1 2 567 | 49 3 49 | 56 67 8 8 C69 356 | 2 1 7 | 45 D36 469 C379 C79 4 | 6 5 8 | 1 237 A29 --------------+---------------+-------------- 5 14 9 | 3 7 26 | 8 246 A126 26 3 68 | 5 48 1 | 9 246 7 267 14 678 | 48 9 26 | 3 5 A126 --------------+---------------+-------------- B69 5 1 | 7 2 49 | B46 8 3 36...