The New Sudoku Players' Forum

[gurth]

This should be a lot easier than it looks, as SE needs only a few chains to do it:

Code: Select all

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

 




[Leren]

Couldn't find a 1 Stepper - here's a 2 Stepper :

Code: Select all

*--------------------------------------------------------------------------------*
| 5       149     1489-3   | 68      2       468      | 7      f349     146      |
| 2489    6       14789    | 3       45789   478      | 159     2459    1245     |
| 2349    2479    3479     | 567     4579    1        |e3569    8       2456     |
|--------------------------+--------------------------+--------------------------|
| 468     3       4678     | 12678   1478    24678    | 158     257     9        |
| 1       479     4789     | 278    c3478    5        |d38      6       278      |
| 68      5       2        | 9       1378    3678     | 4       37      178      |
|--------------------------+--------------------------+--------------------------|
| 7       24     a346      | 258    b358     9        | 568     1       4568     |
| 349     149     5        | 178     6       378      | 2       479     478      |
| 269     8       169      | 4       157     27       | 569     579     3        |
*--------------------------------------------------------------------------------*

(3) r7c3 = r7c5 - r5c5 = r5c7 - r3c7 = (3) r1c8 => - 3 r1c3;

Followed by some basics, then

Code: Select all

*--------------------------------------------------------------------------------*
| 5       149     1489     | 68      2       468      | 7       3       146      |
| 248     6       1478     | 3       45789   478      | 159     2459    1245     |
| 234     247C    347      |a567     4579    1        | 569     8       2456     |
|--------------------------+--------------------------+--------------------------|
| 468     3       4678     | 12678a  1478    24678    | 158     25      9        |
| 1       479B    4789     | 278A    478     5        | 3       6       28       |
| 68      5       2        | 9       138     368      | 4       7       18       |
|--------------------------+--------------------------+--------------------------|
| 7      c2-4dD   346      |b25      35      9        | 568     1       4568     |
| 349     14c     5        | 18b     6       38       | 2       49      7        |
| 269     8       16       | 4       157     27       | 569     59      3        |
*--------------------------------------------------------------------------------*

Kraken Column 4 Digit 7:

7 r3c4 - 5 r3c4 = (5-2) r7c4                 = 2 r7c2;

7 r4c4 - 1 r4c4 = r8c4 - (1=4) r8c2 - 4 r7c2 = 2 r7c2;

7 r5c4 - r5c2 = (7-2) r3c2                   = 2 r7c2; => - 4 r7c2; stte

Leren

[pjb]

Couldn't find single, so here's two:

Code: Select all

 5       149    d13489  | 68     2      468    | 7     c349    146   
 2489    6       14789  | 3      45789  478    | 159    2459   1245   
 2349    2479    3479   | 567    4579   1      |b3569   8      2456   
------------------------+----------------------+---------------------
 468     3       4678   | 12678  1478   24678  | 158    257    9     
 1       479     4789   | 278    478-3  5      |a38     6      278   
 68      5       2      | 9      1378   3678   | 4      37     178   
------------------------+----------------------+---------------------
 7       24     e346    | 258   f358    9      | 568    1      4568   
 349     149     5      | 178    6      378    | 2      479    478   
 269     8       169    | 4      157    27     | 569    579    3     


(3)r5c7 = r3c7 - r1c8 = r1c3 - r7c3 = r7c5 => -3 r5c5; leading to
8s at r8c4 and r8c6 only ones in row.
9s at r1c2 and r1c3 only ones in row.
9s at r8c1 and r9c1 only ones in column, giving:

Code: Select all

 5      d149     1489   | 68     2      468    | 7      3      146   
 248     6       1478   | 3      45789  478    | 159    2459   1245   
 234    b247     347    | 567    4579   1      | 569    8      2456   
------------------------+----------------------+---------------------
 468     3       4678   | 12678  1478   24678  | 158    25     9     
 1      c479     4789   |g278    478    5      | 3      6      28     
 68      5       2      | 9      138    368    | 4      7      18     
------------------------+----------------------+---------------------
 7      a24      346    | 5-2    35     9      | 568    1      4568   
 349    e14      5      |f18     6      38     | 2      49     7     
 269     8       16     | 4      157    27     | 569    59     3     


(2)r7c2 = (2-7)r3c2 = (7-9)r5c2* = (9-1)r1c2 = r8c2 - (1=8)r8c4 - (78=2)r5c4* => -2 r7c4; stte

Phil

[daj95376]

Since both of the above solutions contain a network step, I'll add my solver's network single-stepper.

Code: Select all

 +-----------------------------------------------------------------------+
 |  5      149    13489  |  68     2      468    |  7      349    146    |
 |  2489   6      14789  |  3      45789  478    |  159    2459   1245   |
 |  2349   2479   3479   |  567    4579   1      |  3569   8      2456   |
 |-----------------------+-----------------------+-----------------------|
 |  468    3      4678   |  12678  1478   24678  |  158    257    9      |
 |  1      479    4789   |  278    3478   5      |  38     6      278    |
 |  68     5      2      |  9      1378   3678   |  4      37     178    |
 |-----------------------+-----------------------+-----------------------|
 |  7      24     346    |  258    358    9      |  568    1      4568   |
 |  349    149    5      |  178    6      378    |  2      479    478    |
 |  269    8      169    |  4      157    27     |  569    579    3      |
 +-----------------------------------------------------------------------+
 # 132 eliminations remain

 =3r8c6 =3r3c1 =3r1c8 =7r6c8 =7r8c9 =8r8c4 =5r7c5 =2r7c4 =2r3c2 =7r5c2 -> [r5c4]=EMPTY  =>  -3 r8c6


_

[JC Van Hay]

After basics, analysis of the puzzle from the 2 solutions of the 3s gives this one-stepper ...

Code: Select all

+------------------+------------------+-----------------+
| 5    19     19   | 68    2     468  | 7    3     46   |
| 248  6      478  | 3     4579  47   | 159  2459  1245 |
| 234  4(27)  347  | 567   4579  1    | 69   8     2456 |
+------------------+------------------+-----------------+
| 468  3      4678 | 1267  1478  2467 | 158  25    9    |
| 1    49(7)  4789 | (27)  48    5    | 3    6     28   |
| 68   5      2    | 9     138   36   | 4    7     18   |
+------------------+------------------+-----------------+
| 7    4(2)   346  | 5-2   35    9    | 568  1     4568 |
| 349  14     5    | 18    6     38   | 2    49    7    |
| 269  8      16   | 4     157   27   | 569  59    3    |
+------------------+------------------+-----------------+


M-Wing [(2)r73c2 (7)r35c2 (72)r5c4] - 2r7c4; stte

[bat999]

Code: Select all

.---------------------.----------------------.-------------------.
|  5     149    13489 | 68      2      468   |  7     349   146  |
|  2489  6      14789 | 3       45789  478   |  159   2459  1245 |
| *2349  2479  *3479  | 567     4579   1     | *3569  8     2456 |
:---------------------+----------------------+-------------------:
|  468   3      4678  | 12678   1478   24678 |  158   257   9    |
|  1     479    4789  | 278    *3478   5     | *3-8   6     278  |
|  68    5      2     | 9       1378   3678  |  4     37    178  |
:---------------------+----------------------+-------------------:
|  7     24    *346   | 258     *358    9    |  568   1     4568 |
|  349   149    5     | 178     6      378   |  2     479   478  |
|  269   8      169   | 4       157    27    |  569   579   3    |
'---------------------'----------------------'-------------------'

Hi gurth

There's a problem if r5c7 is not 3.
r5c7<>3->r5c5=3->r7c5<>3->r7c3=3->r3c3<>3->r3c1=3->r3c7<>3
Now there are no 3's left in column 7.
=> -8 r5c7

After some basic moves...

Code: Select all

.----------------.---------------------.-----------------.
| 5    149  1489 | 68     2      468   | 7    3     146  |
| 248  6    1478 | 3      45789  478   | 159  2459  1245 |
| 234  247  347  | 567    4579   1     | 569  8     2456 |
:----------------+---------------------+-----------------:
| 468  3    4678 | 12678  1478   24678 | 158  25    9    |
| 1    479  4789 | 278    478    5     | 3    6     28   |
| 68   5    2    | 9      138    368   | 4    7     18   |
:----------------+---------------------+-----------------:
| 7    24   346  | 25     35     9     | 568  1     4568 |
| 349  14   5    | 18     6      38    | 2    49    7    |
| 269  8    16   | 4      157    27    | 569  59    3    |
'----------------'---------------------'-----------------'

I plodded on after that to solve the problem OK.
Chipped away at it till it surrendered, several more steps.

Afterwards when I asked HoDoKu for some hints.
It needed...
Two Finned X-Wings, a Finned Swordfish, two Sue de Coqs and a W-Wing.
What a show-off!

[gurth]

Hi Bat,
This puzzle is still keeping me very busy as I try to get it all in one CW diagram. I just gave it my first free hour of the day - increasing the length of my singles chain from about 25 links to 43 links - there are still a few cells on the board I haven't reached!

Thanks to you for mentioning HoDoKu - I've had some good fun with its library, practising my Finned Franken Swordfish skills!

[gurth]

Finished at last!

CW:
I'll have to comment on this, I think.
I've used up all 52 small and big letters and there are precisely 4 squares which are still unlabelled, all obviously red singles. Suppose we continued with Z1,Z2,Z3,Z4 as labels.
Now every cell contains a red single, and they all add up to a valid solution. Whether you can accept that as a satisfactory solution is up to you - for blue has nowhere been contradicted. Unfortunately I started with Blue Conjugates which had too little to say for themselves. But still, by move (O)(the 41st move!) Blue was still giving Red help: the placing of a Red in the same cell as the conjugate blue made that red a conjugate, which cut the 2 in the same cell, furthering the march of the red singles. Later - at what point exactly makes no difference - it was just all unaided red singles.

My main aim has been achieved - to find the solution in one diagram.

Note: the solver does not need the green lines. They were added later, to help the reader find the next letter.
Next I'll have to try 535se71.

[DonM]

I plodded on after that to solve the problem OK.
Chipped away at it till it surrendered, several more steps.

Afterwards when I asked HoDoKu for some hints.
It needed...
Two Finned X-Wings, a Finned Swordfish, two Sue de Coqs and a W-Wing.
What a show-off!

Since you apparently solved puzzle, it might be better to show your solution rather than a computer solver's.

[bat999]

... show your solution...

Hi
You would do well to study the solutions already posted above by other forum members.

The steps that I used would not help, even if I could remember what they were.

[DonM]

... show your solution...

Hi
You would do well to study the solutions already posted above by other forum members.

The steps that I used would not help, even if I could remember what they were.

I hate when that happens.