The New Sudoku Players' Forum

[ArkieTech]

Code: Select all

 *-----------*
 |..1|..4|6.9|
 |.3.|.2.|.7.|
 |..8|6..|...|
 |---+---+---|
 |8..|...|4..|
 |.1.|...|.5.|
 |..3|...|..6|
 |---+---+---|
 |...|..7|5..|
 |.7.|.9.|.8.|
 |5.4|1..|7..|
 *-----------*


Play/Print this puzzle online

[SCLT]

Many XY-Chains today, so here's something silly:

Code: Select all

+-----------+--------------------+------------------+
| 27  25  1 | 8   57     4       | 6      3   9     |
| 4   3   6 | 9   2      15      | 18     7   [1]58 |
| 79 b59  8 | 6   1[5]7  3       | 2      4  a15    |
+-----------+--------------------+------------------+
| 8  c29  5 | 3   6      19      | 4     d12  7     |
| 6   1   7 | 24  48     2[8]9   | 3[8]9  5   38    |
| 29  4   3 | 7  f15    f[19]5-8 | 89    e12  6     |
+-----------+--------------------+------------------+
| 13  8   9 | 24  34     7       | 5      6   12[3] |
| 13  7   2 | 5   9      6       | 13     8   4     |
| 5   6   4 | 1   38     28      | 7      9   23    |
+-----------+--------------------+------------------+


BUG+7 (only the long common partial chain for the last two nodes in the SIS shown in grid):

Code: Select all

8r5c6 - r6c6
||
(1|9)r6c6 - 8r6c6
||
5r3c5 - 5r6c5 = r6c6 - 8r6c6
||
3r7c9 - (3=4)r7c5 - (4=8)r5c5 - r6c6
||
8r5c7 - (8=1)r2c7 - (1=5)r3c9 - (5=9)r3c2 - (9=2)r4c2 - (2=1)r4c8 - r6c8 = (15)r6c56 - 8r6c6
||
1r2c9 - (1=5)r3c9 - (5=9)r3c2 - (9=2)r4c2 - (2=1)r4c8 - r6c8 = (15)r6c56 - 8r6c6

-8r6c6; stte

[SpAce]

Code: Select all

.-----------.-------------------.---------------.
| 27  25  1 | 8   57    4       |  6    3   9   |
| 4   3   6 | 9   2    a1[5]    | a18   7   158 |
| 79  59  8 | 6   157   3       |  2    4   15  |
:-----------+-------------------+---------------:
| 8   29  5 | 3   6     19      |  4    12  7   |
| 6   1   7 | 24  48    289     |  389  5   38  |
| 29  4   3 | 7   15   b1(8)9-5 | b89   12  6   |
:-----------+-------------------+---------------:
| 13  8   9 | 24  34    7       |  5    6   123 |
| 13  7   2 | 5   9     6       |  13   8   4   |
| 5   6   4 | 1   38    28      |  7    9   23  |
'-----------'-------------------'---------------'


H3-Wing:

(5=18)r2c67 - r6c7 = (8)r6c6 => -5 r6c6; stte

It was actually found through this BUG+7:

Code: Select all

(1|9)r6c6
||
(1)r2c9 - (1=5)r2c6
||
(5)r3c5 - (5=18)r2c67 - r6c7 = (8)r6c6
||
(8)r5c6 - r6c6 = (81)r62c7 - (1=5)r2c6
||
(8)r5c7 - r6c7 = (8)r6c6
||
(3)r7c9 - (3=8)r5c9 - r6c7 = (8)r6c6

=> -5 r6c6; stte

[Cenoman]

Code: Select all

 +-----------------+--------------------+-------------------+
 |  27  c25   1    |  8   b57    4      |  6     3    9     |
 |  4    3    6    |  9    2     5-1*   | a18    7    158*  |
 |  79   59   8    |  6    157*  3      |  2     4    15*   |
 +-----------------+--------------------+-------------------+
 |  8   c29   5    |  3    6   da19     |  4     12   7     |
 |  6    1    7    |  24   48    289    |  389   5    38    |
 |  29   4    3    |  7    15*   1589*  |  89    12   6     |
 +-----------------+--------------------+-------------------+
 |  13   8    9    |  24   34    7      |  5     6    123   |
 |  13   7    2    |  5    9     6      |  13    8    4     |
 |  5    6    4    |  1    38    28     |  7     9    23    |
 +-----------------+--------------------+-------------------+

DP(15)r23c9, b2p68, r6c56 (BUG-lite) using externals
(1)r2c7|r4c6 == (5)r1c5 - (5=29)r14c2 - (9=1)r4c6 => -1 r2c6; ste

[Sudtyro2]

Code: Select all

+--------------+-----------------+--------------+
| 27  a25   1  | 8  a5+7   4     | 6   3   9    |
| 4    3    6  | 9   2    a15    | 18  7   158  |
| 79   59   8  | 6   157   3     | 2   4   15   |
+--------------+-----------------+--------------+
| 8   b29   5  | 3   6    b19    | 4   12  7    |
| 6    1    7  | 24  48    289   | 389 5   38   |
| 29   4    3  | 7   15    1589  | 89  12  6    |
+--------------+-----------------+--------------+
| 13   8    9  | 24  34    7     | 5   6   123  |
| 13   7    2  | 5   9     6     | 13  8   4    |
| 5    6    4  | 1   38    28    | 7   9   23   |
+--------------+-----------------+--------------+

Myth's CoALS rule applied to the two overlapping ALS tagged (a).
(57=12)r1c25,r2c6 - (1|2=9)r4c26[contradiction] => +7 r1c5; stte.

SteveC

[SpAce]

Hi Steve,

(57=12)r1c25,r2c6 - (1|2=9)r4c26[contradiction] => +7 r1c5; stte.

I have no problem with your logic, and very little with anything else either. I'm just wondering if the contradiction condition could be shown more clearly. As written, (9)r4c26 is not an obvious contradiction per se, because it just means 9 is in at least one of those cells (OR). What you mean is AND. Thus, maybe something like this:

(1|2)r4c26 = (9)r2c2&r2c6[contradiction]

Btw, you could also flip it around and use (9)r2c2&r2c6 as a DP and the 1 and 2 as guardians. Or what the hell, why not use externals:

(9)r2c2&r2c6 [DP]
||
(9)r6c1 - (9=72)r31c1 - (21=57)r1c25,r2c6
||
(9)r56c6 - (9=1)r4c6 - (12=57)r1c25,r2c6

=> +7 r1c5

Why make it simple if you can make it complicated?

[Sudtyro2]

(57=12)r1c25,r2c6 - (1|2=9)r4c26[contradiction] => +7 r1c5; stte.

Hi SpAce,
Thx for the feedback!
I wasn't sure how to properly notate the contradiction, but writing - (1|2= ... does clearly indicate that BOTH digits 1 and 2 are false. So, a digit 9 left in both cells of r4c26 would be a clear impossibility. But I have no problem with your (1|2)r4c26 = (9)r2c2&r2c6[contradiction] notation, either!

SteveC