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[ArkieTech]

Code: Select all

 *-----------*
 |.9.|5.1|...|
 |..2|.63|...|
 |.4.|...|...|
 |---+---+---|
 |36.|...|71.|
 |7..|...|..9|
 |.89|...|.53|
 |---+---+---|
 |.1.|.9.|.7.|
 |...|64.|1..|
 |...|2.8|.4.|
 *-----------*


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[Leren]

Code: Select all

*--------------------------------------------------------------*
|b68    9     367    | 5     278   1      | 2368  2368  4      |
|b158   7-5   2      | 4     6     3      | 589   89    17     |
|b1568  4     13567  | 79    278   29     | 23568 2368  17     |
|--------------------+--------------------+--------------------|
| 3     6     4      | 89    5     29     | 7     1     28     |
| 7    a25    15     | 18    3     46     | 2468  268   9      |
|b12    8     9      | 17    27    46     | 46    5     3      |
|--------------------+--------------------+--------------------|
| 4     1     68     | 3     9     5      | 28    7     268    |
| 29    23    58     | 6     4     7      | 1     39    58     |
| 569   357   567    | 2     1     8      | 39    4     56     |
*--------------------------------------------------------------*

ALS XZ Rule: X = 2, Z = 5: (5=2) r5c2 - (2=5) r1236c1 => - 5 r2c2; stte

Leren

[SteveG48]

Code: Select all

 *--------------------------------------------------------------------*
 | 68     9      367    | 5      278    1      | 2368   2368   4      |
 | 158   b57     2      | 4      6      3      | 589    89    c17     |
 | 1568   4      13567  | 9-7    278    29     | 23568  2368  d17     |
 *----------------------+----------------------+----------------------|
 | 3      6      4      | 89     5      29     | 7      1      28     |
 | 7     b25     15     | 18     3      46     | 2468   268    9      |
 |a12     8      9      |a17     27     46     | 46     5      3      |
 *----------------------+----------------------+----------------------|
 | 4      1      68     | 3      9      5      | 28     7      268    |
 | 29     23     58     | 6      4      7      | 1      39     58     |
 | 569    357    567    | 2      1      8      | 39     4      56     |
 *--------------------------------------------------------------------*


(7=12)r6c14 - (2=57)r25c2 - 7r2c9 = 7r3c9 => -7 r3c4 ; stte

[pjb]

Code: Select all

 68      9       367    | 5      278    1      | 2368   2368   4     
 58-1   a57      2      | 4      6      3      | 589    89    a17     
 1568    4       13567  | 79     278    29     | 23568  2368   17     
------------------------+----------------------+---------------------
 3       6       4      | 89     5      29     | 7      1      28     
 7      b25      15     | 18     3      46     | 2468   268    9     
b12      8       9      | 17     27     46     | 46     5      3     
------------------------+----------------------+---------------------
 4       1       68     | 3      9      5      | 28     7      268   
 29      23      58     | 6      4      7      | 1      39     58     
 569     357     567    | 2      1      8      | 39     4      56     



(1=5)r2c29 - (5=1)r5c2,r6c1 => -1 r2c1; stte

Phil

[Marty R.]

Code: Select all

+----------------+-----------+----------------+
| 68   9   367   | 5  278 1  | 2368  2368 4   |
| 158  57  2     | 4  6   3  | 589   89   17  |
| 1568 4   13567 | 79 278 29 | 23568 2368 17  |
+----------------+-----------+----------------+
| 3    6   4     | 89 5   29 | 7     1    28  |
| 7    25  15    | 18 3   46 | 2468  268  9   |
| 12   8   9     | 17 27  46 | 46    5    3   |
+----------------+-----------+----------------+
| 4    1   68    | 3  9   5  | 28    7    268 |
| 29   23  58    | 6  4   7  | 1     39   58  |
| 569  357 567   | 2  1   8  | 39    4    56  |
+----------------+-----------+----------------+


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(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

[Sudtyro2]

(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

Just a notation question...
Doesn't the AIC, as written, imply only -9r4c4?
To get the (secondary) 8r4c4 placement directly, you'd need a discontinuous loop. One could maybe replace your first node with something like...
(8=97)r34c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

SteveC

[Marty R.]

(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

Just a notation question...
Doesn't the AIC, as written, imply only -9r4c4?
To get the (secondary) 8r4c4 placement directly, you'd need a discontinuous loop. One could maybe replace your first node with something like...
(8=97)r34c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

SteveC

I don't know if the AIC implies only -9. As far as I'm concerned, 7 in r3c4 proves an 8 in r4c4. And if the 7 is false then it's a 9 which also yields 8 in r4c4. My understanding of the purpose of notation is to tell the reader how the solution was arrived at. I can't see why the notation doesn't serve that purpose. You say toh-MAY-toh, I say toh-MAH-toh, you say <>9, I said =8.

[Sudtyro2]

(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

Just a notation question...
Doesn't the AIC, as written, imply only -9r4c4?
To get the (secondary) 8r4c4 placement directly, you'd need a discontinuous loop. One could maybe replace your first node with something like...
(8=97)r34c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

SteveC

I don't know if the AIC implies only -9. As far as I'm concerned, 7 in r3c4 proves an 8 in r4c4. And if the 7 is false then it's a 9 which also yields 8 in r4c4. My understanding of the purpose of notation is to tell the reader how the solution was arrived at. I can't see why the notation doesn't serve that purpose. You say toh-MAY-toh, I say toh-MAH-toh, you say <>9, I said =8.

Marty, the way I learned it, the real chain is a discontinuous loop with weak-weak inference at the ends, as shown below, but one customarily omits those two final weak links in writing the AIC. Similarly, to place a candidate, one needs a discontinuous loop with strong-strong inference to that candidate at the ends, as suggested earlier. Your chain alone makes the desired elimination, but I think the placement then requires a second step. Read in either direction, these are simply contradiction chains:

9r4c4-(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46-9r4c4=> -9r4c4

(8=97)r34c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

SteveC

[JC Van Hay]

(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=98)r4c46=> 8r4c4

or, better, [(9=7)r3c4-r3c9=r2c9-(7=52)r25c2-r5c78=r4c9-(2=9)r4c6]-(9=8)r4c4 where the square brackets contain the AIC. Note that such notation is often used to write down an AAIC : ...=[AIC]-...