The New Sudoku Players' Forum

[SteveG48]

Code: Select all

 *-----------*
 |.2.|..7|...|
 |4..|...|..5|
 |9.8|...|4..|
 |---+---+---|
 |..3|.9.|.6.|
 |...|65.|...|
 |.8.|.1.|9..|
 |---+---+---|
 |..5|.6.|7.4|
 |2..|...|..9|
 |...|3..|.5.|
 *-----------*


[jco]

Hello,

After basics

1. UR(19) r27 c46 with mixed internal, externals => -8 r89c5

Code: Select all

  1   2     3   4     5    6     7     8     9
.-------------+-----------------+-------------------.
| 36  2     1 | 5     4    7    | 368   9     368   | 1
| 4   36    7 |*1928  238 *19(6)| 1236  123   5     | 2
| 9   5     8 |(1)2   23   16   | 4     1237  12367 | 3
|-------------+-----------------+-------------------|
| 1   4     3 | 7     9    28   | 5     6     28    | 4
| 7   9     2 | 6     5    38   | 138   4     138   | 5
| 5   8     6 | 4     1    23   | 9     237   237   | 6
|-------------+-----------------+-------------------|
| 38  13    5 |*1928  6   *19   | 7     1238  4     | 7
| 2   1367  4 |(1)8   7-8  5    | 136   138   9     | 8
| 68  167   9 | 3     27-8 4    | 126   5     126   | 9
'-------------+-----------------+-------------------'

(1)r3c4-(1=8)r8c4
||
(1)r8c4-(1=238)b2p578
||
(6)r2c6-(6=1238)b2p5789

ste

First time writing an UR move here. I hope this is right.

Regards,
jco
EDIT: corrected typo and changed notation to b.p coordinates (thanks Cenoman!). All those numbers on the top and side of the board did not help avoiding this typo!

[Leren]

Code: Select all

*-----------------------------------------------*
| 36 2    1 | 5     4     7   | 368  9    368   |
| 4  36   7 |e1289 f38-2 d169 | 1236 123  5     |
| 9  5    8 | 12    23    16  | 4    1237 12367 |
|-----------+-----------------+-----------------|
| 1  4    3 | 7     9     28  | 5    6    28    |
| 7  9    2 | 6     5     38  | 138  4    138   |
| 5  8    6 | 4     1     23  | 9    237  237   |
|-----------+-----------------+-----------------|
| 38 13   5 |b1289  6    c19  | 7    1238 4     |
| 2  1367 4 | 18    78    5   | 136  138  9     |
| 68 167  9 | 3    a27-8  4   | 126  5    126   |
*-----------------------------------------------*

(2) r9c5 = (2-9) r7c4 = r7c6 - r2c6 = (9-8) r2c4 = (8) r2c5 => - 2 r2c5; - 8 r9c5; stte

Leren

[Cenoman]

Code: Select all

 +-------------------+---------------------+------------------------+
 |  36   2      1    |  5      4     7     |  368    9      368     |
 |  4    36     7    |  1289   238   169   |  1236   123    5       |
 |  9    5      8    | c12     23    16    |  4      1237   12367   |
 +-------------------+---------------------+------------------------+
 |  1    4      3    |  7      9     28    |  5      6      28      |
 |  7    9      2    |  6      5     38    |  138    4      138     |
 |  5    8      6    |  4      1     23    |  9      237    237     |
 +-------------------+---------------------+------------------------+
 |  38   13     5    | a189-2  6    a19    |  7      1238   4       |
 |  2    1367   4    | b18     78    5     |  136    138    9       |
 |  68   167    9    |  3      278   4     |  126    5      126     |
 +-------------------+---------------------+------------------------+

Almost hidden pair:
(91)r7c46 = r8c4 - (1=2)r3c4 => -2r7c4; ste

[Cenoman]

1. UR(19) r27 c46 with mixed internal, externals => -8 r89c5

(1)r3c4-(1=8)r7c4
||
(1)r8c4-(1=238)r3c45.r2c5
||
(6)r2c6-(6=1238)r3c456.r2c5

ste

First time writing an UR move here. I hope this is right.

Hi jco,

I guess there is a typo in your first chain ...(1=8)r8c4.
Nice UR move ! Yes it is right. May be you have noticed that your kraken-UR is presented like a Death Blossom, but I don't know if the pattern Death Blossom-UR has ever been proposed !

A minor comment about notation. On this forum, some players (myself included) write Box-ALS's with b.p... coordinates,
where b is followed by the number of the box and p by the numbers of the ALS cells within the box (numbering from up-left to bottom-right)
Your kraken would then read:
(1)r3c4-(1=8)r8c4
||
(1)r8c4-(1=238)b2p578
||
(6)r2c6-(6=1238)b2p5789
=> -8 r89c5; ste

Note that you could have used externals only: 1r38c4 and 1 r3c6:
(8=1)r8c4 - (1)r3c4 == (1)r8c4|r3c6 - (1=238)b2p578 => -8 r89c5; ste

[jco]

Hello Cenoman,

1. UR(19) r27 c46 with mixed internal, externals => -8 r89c5

(1)r3c4-(1=8)r7c4
||
(1)r8c4-(1=238)r3c45.r2c5
||
(6)r2c6-(6=1238)r3c456.r2c5

ste

First time writing an UR move here. I hope this is right.

Hi jco,

I guess there is a typo in your first chain ...(1=8)r8c4.
Nice UR move ! Yes it is right. May be you have noticed that your kraken-UR is presented like a Death Blossom, but I don't know if the pattern Death Blossom-UR has ever been proposed !

A minor comment about notation. On this forum, some players (myself included) write Box-ALS's with b.p... coordinates,
where b is followed by the number of the box and p by the numbers of the ALS cells within the box (numbering from up-left to bottom-right)
Your kraken would then read:
(1)r3c4-(1=8)r8c4
||
(1)r8c4-(1=238)b2p578
||
(6)r2c6-(6=1238)b2p5789
=> -8 r89c5; ste

Note that you could have used externals only: 1r38c4 and 1 r3c6:
(8=1)r8c4 - (1)r3c4 == (1)r8c4|r3c6 - (1=238)b2p578 => -8 r89c5; ste

Thank you for pointing out the typo and for the insightful comments!
I did not notice at all the connection to Death Blossom (interesting!).
I corrected the typo and changed to notation using b.p coordinates.
Also, many thanks for mentioning the possibility with externals only.
Best regards,
jco

[ghfick]

WXYZ-Wing: 1238 in r3c45, r2c5, r8c4, Pivot Cell is r3c4 => r89c5, r2c4<>8

[AnotherLife]

I think that the above elimination has more to do with Almost Locked Sets than Unique Rectangles. We can consider:
1. Almost Locked Set XZ-Rule: A=r8c4 {18}, B=r23c5,r3c4 {1238}, X=1, Z=8 => r2c4,r89c5<>8 https://disk.yandex.ru/i/WLwP906FpYz6Eg
or 2. Death Blossom: [r3c4], -1- r8c4 {18}, -2- r23c5 {238} => r2c4,r89c5<>8 https://disk.yandex.ru/i/qg3ww0p_l7G_QQ

Actually, we do not have to apply the methods of 'Extreme' category when simpler methods are available (2-String Kite, Hidden Rectangle and XY-Wing).

[pjb]

Code: Select all

 36      2       1      | 5      4      7      | 368    9      368   
 4       36      7      | 1289   238    169    | 1236   123    5     
 9       5       8      | 12     23     16     | 4      1237   12367 
------------------------+----------------------+---------------------
 1       4       3      | 7      9      28     | 5      6      28     
 7       9       2      | 6      5      38     | 138    4      138   
 5       8       6      | 4      1      23     | 9      237    237   
------------------------+----------------------+---------------------
b38     a13      5      | 289-1  6      9-1    | 7     c1238   4     
 2       367-1   4      |e18     78     5      | 136   d138    9     
 68      167     9      | 3      278    4      | 126    5      126   


(1=3)r7c2 - (3=8)r7c1 - (8)r7c8 = (8)r8c8 - (8=1)r8c4 => -1 r7c46, r8c2; stte

Phil