The New Sudoku Players' Forum

[ArkieTech]

Code: Select all

 *-----------*
 |...|.4.|6..|
 |...|6.5|...|
 |.5.|...|18.|
 |---+---+---|
 |7.6|..2|59.|
 |.1.|.9.|.7.|
 |.95|7..|4.8|
 |---+---+---|
 |.62|...|.3.|
 |...|1.9|...|
 |..8|.2.|...|
 *-----------*


Play/Print this puzzle online

[SteveG48]

Code: Select all

 *-----------------------------------------------------------------------------*
 | 38      2378    1379    | 29      4       18      | 6       25      23579   |
 | 348     23478   13479   | 6       18      5       | 2379   g24      23479   |
 | 6       5      i49      | 29      37      37      | 1       8      h249     |
 *-------------------------+-------------------------+-------------------------|
 | 7       348     6       | 348     138     2       | 5       9      L3-1     |
 | 2348    1      j34      | 5       9       3468    |k23      7      k236     |
 | 23      9       5       | 7      e136     136     | 4     af126     8       |
 *-------------------------+-------------------------+-------------------------|
 | 19      6       2       | 48      5       478     | 789     3       1479    |
 | 5       347     347     | 1      d3678    9       | 278     246     2467    |
 | 19      347     8       | 34      2      c3467    | 79     b1456   c145679  |
 *-----------------------------------------------------------------------------*


(1*)r6c8 = (1-56)r9c8 = (6)r9c69 - r8c5 = r6c5 - (6*1=2)r6c8 - (2=4)r2c8 - r3c9 = r3c3 - (4=3)r5c3 - r5c79 = (3)r4c9 => -1 r4c9 ; stte

[Leren]

Code: Select all

*--------------------------------------------------------------------------------*
| 38      2378    1379     | 29      4       18       | 6       25      23579    |
| 348     23478   13479    | 6       18      5        | 2379   B24      23479    |
| 6       5      D49       | 29      37      37       | 1       8      C249      |
|--------------------------+--------------------------+--------------------------|
| 7       348     6        | 348     138     2        | 5       9     Gb3-1h     |
| 2348    1      E34       | 5       9       3468c    |F23      7      F236b     |
| 23      9       5        | 7       136     136      | 4     Aa126agA  8        |
|--------------------------+--------------------------+--------------------------|
| 19      6       2        | 48      5       478      | 789     3       1479     |
| 5       347     347      | 1       3678    9        | 278     246     2467     |
| 19      347     8        | 34      2       3467d    | 79      1456fB  145679e  |
*--------------------------------------------------------------------------------*

Kraken Cell r6c8:

1 r6c8                                                          - 1 r4c9;

2 r6c8 - (2=4) r2c8 - r3c9 = r3c3 - (4=3) r5c3 - r5c79 = r4c9   - 1 r4c9;

6 r6c8 - r5c9 = r5c6 - r9c6 = r9c9 - 5 r9c9 = (5-1) r9c8 = r6c8 - 1 r4c9; => - 1 r4c9; stte
       |                    |
        \            - r9c8/

Leren

[ArkieTech]

Code: Select all

 *-----------------------------------------------------------------------------*
 | 38      2378    1379    | 29      4      b18      | 6       25      23579   |
 |*348     23478   1379-4  | 6      a18      5       |w2379    24      23479   |
 | 6       5       9-4     | 29      37     w37      | 1       8       249     |
 |-------------------------+-------------------------+-------------------------|
 | 7       348     6       | 348     138     2       | 5       9       13      |
 |d238-4   1      w34      | 5       9      c3468    |w23      7       236     |
 | 23      9       5       | 7       136     136     | 4       126     8       |
 |-------------------------+-------------------------+-------------------------|
 | 19      6       2       | 48      5       478     | 789     3       1479    |
 | 5       347     347     | 1       3678    9       | 278     246     2467    |
 | 19      347     8       | 34      2       3467    | 79      1456    145679  |
 *-----------------------------------------------------------------------------*
[8r2c5=r1c6=r5c6=8r5c1]-(8=43)r2c1[ww:43r2c1,r5c3,3r25c7] => -4r34c3,r5c1; lclste


[eleven]

I have the same problem here as with aran's chain in the other thread. Obviously 2 steps (kite and w-wing) are written in one chain.
The point is, that the chain includes a contradiction:
[8r2c5=r1c6-r5c6=8r5c1]-8r2c1...
8r2c1 is no option, because it contradicts to both sides of the chain.
So i would wish a rule, that deductions must not contain a contradiction, but that has to be counted as an own step. Otherwise not the solving, but the formulating would be the art.

[ArkieTech]

I have the same problem here as with aran's chain in the other thread. Obviously 2 steps (kite and w-wing) are written in one chain.
The point is, that the chain includes a contradiction:
[8r2c5=r1c6-r5c6=8r5c1]-8r2c1...
8r2c1 is no option, because it contradicts to both sides of the chain.
So i would wish a rule, that deductions must not contain a contradiction, but that has to be counted as an own step. Otherwise not the solving, but the formulating would be the art.

Thanks;

I've been looking for a way to show this in Eureka without much luck.

How about:

8r2c5=r1c6=r5c6=8r5c1 => -(8=43)r2c1 => ww:43r2c1,r5c3,3r25c7 => -4r34c3,r5c1; lclste

[eleven]

If you write it aran-like as
8r5c1=r5c6-r1c6=8r2c5-(8=34r2c1)[ww:43r2c1,r5c3,3r25c7] => r5c1<>4,
it is a perfect AIC, it has alternating inferences, all correct, starting and ending with a strong link, and probably most of you would accept it.

The disfigurement in my eyes is, that the chain uses a digit, which is already eliminated by a part of the chain.
My opinion is, that in fact these are 2 short chains, and i find them as good as one long.

There is another situation (i forgot the name), when chains are continued after an elimination already can be made. A simple sample is, that you have 3 strong links, and you already can eliminate a digit after 2 of them, and another one after the third link. This is, what i would clearly accept, because the second elimination does not depend on the first one, and no digit of the chain is eliminated by a part of it.

[DonM]

There is another situation (i forgot the name), when chains are continued after an elimination already can be made. A simple sample is, that you have 3 strong links, and you already can eliminate a digit after 2 of them, and another one after the third link. This is, what i would clearly accept, because the second elimination does not depend on the first one, and no digit of the chain is eliminated by a part of it.

I believe you're thinking of a 'pausing chain'.

[gurth]

Code: Select all


 *-----------------------------------------------------------------------------*
 | 38      2378    1379    | 29      4       18      | 6       25      23579   |
 | e348    23478   13479   | 6       k18     5       | d2379   24      23479   |
 | 6       5       49      | 29      37      37      | 1       8       249     |
 *-------------------------+-------------------------+-------------------------|
 | 7       348     6       | 348     j138    2       | 5       9      i13      |
 | a2348   1       b34     | 5       9       3468    | c23     7       f236    |
 | h23     9       5       | 7       136     136     | 4       g126    8       |
 *-------------------------+-------------------------+-------------------------|
 | 19      6       2       | 48      5       478     | 789     3       1479    |
 | 5       347     347     | 1       3678    9       | 278     246     2467    |
 | 19      347     8       | 34      2       3467    | 79      1456    145679  |
 *-----------------------------------------------------------------------------*

451>353>257>327>821.
451>353>257>659>168(451>-251>261)-149>145>825

=> -451, stte.