The New Sudoku Players' Forum

[yzfwsf]

Code: Select all

,-------------------,-------------------,----------------,
| 78     1    2     | 3     59     59   | 78    4    6   |
| 4      5    6     | 8     7      2    | 13    19   39  |
| 3      79   789   | 6     4      1    | 78    2    5   |
:-------------------+-------------------+----------------:
| 1      379  4     | 579   3569   8    | 36    679  2   |
| 25679  367  3579  | 279   1369   679  | 1346  8    479 |
| 2679   8    379   | 279   12369  4    | 5     179  379 |
:-------------------+-------------------+----------------:
| 569    2    579   | 1     8      5679 | 46    3    47  |
| 56789  346  35789 | 4579  569    5679 | 2     567  1   |
| 567    46   1     | 2457  256    3    | 9     567  8   |
'-------------------'-------------------'----------------'

This PM may have a or more rank 0 structure with 14 eliminations.

[marek stefanik]

Two eliminations short:

Code: Select all

,-------------------,-------------------,----------------,
| 78     1    2     | 3     59     59   | 78    4    6   |
| 4      5    6     | 8     7      2    | 13    19   39  |
| 3      79   789   | 6     4      1    | 78    2    5   |
:-------------------+-------------------+----------------:
| 1      79–3 4     | 579  c3569   8    |b36    679  2   |
|e259–67 367  3579  | 279  d13–69  679  | 134–6 8    479 |
|e269–7  8    379   | 279  d136–29 4    | 5     179  379 |
:-------------------+-------------------+----------------:
|f569    2   g579   | 1     8      569–7|a46    3   h47  |
|f56789  346  378–59| 4579  569    5679 | 2     567  1   |
|f567    46   1     | 2457  256    3    | 9     567  8   |
'-------------------'-------------------'----------------'

(4=6)r7c7 – (6=3)r4c7 – 3r4c5 = (13–6)r56c5 = (26–5|9)r56c1 = 59r789c1 – (5|9=7)r7c3 – (7=4)r7c9 – Loop, 8.7 -> 7.2 skfr

Marek

[yzfwsf]

15 Truths-->14 Eliminations
Cell Type Blossom Loop: 579r7c3 => r4c2 <> 3, r8c3,r9c5 <> 5, r5c157,r49c5 <> 6, r56c1,r7c6 <> 7, r56c5,r8c3 <> 9
5r7c3 - (5=3796)b4p2569 - r6c1 = r6c5 - (6=593)r148c5 - (3=6)r4c7 - (6=197)r246c8 - r89c8 = r7c9 - 7r7c3
9r7c3 - r78c1 = 9r56c1

VS yours:
14 t [35,142] 26 Candidates,
10 Truths = {6R6 59C1 4N7 7N379 2B4 13B5}
10 Links = {3r4 7r7 6c7 56n1 56n5 59b7 4b9}
12 Eliminations --> (3r4) => r4c2<>3, (5n1) => r5c1<>6, (5n1) => r5c1<>7, (5n5) => r5c5<>6, (5n5) => r5c5<>9, (6c7) =>
r5c7<>6, (6n1) => r6c1<>7, (6n5) => r6c5<>2, (6n5) => r6c5<>9, (7r7) => r7c6<>7, (5b7) => r8c3<>5, (9b7) =>
r8c3<>9

[pjb]

Code: Select all

 78      1       2      | 3      59     59     | 78     4      6     
 4       5       6      | 8      7      2      | 13C    19B    39D   
 3       79      789    | 6      4      1      | 78     2      5     
------------------------+----------------------+---------------------
 1       379     4      | 579    3569   8      |e36F   a679A   2     
 25679   367     3579   | 279    1369   679    |e1346   8     b479   
 2679    8       379    | 279    12369  4      | 5      179   b379E 
------------------------+----------------------+---------------------
 569     2       579    | 1      8      5679   |d46     3     c47     
 56789   346     35789  | 4579   569    5679   | 2      567    1     
 567     46      1      | 2457   256    3      | 9      567    8     


I just started playing with this method and came up with this cell base blossom loop. Is this OK?

chain1 = (7)r4c8 - (7)r56c9 = (7-4)r7c9 = (4-6)r7c7 = (6)r45c7 - loop => -7 r6c8
chain2 = (9)r4c8 - (9=1)r2c8 - (1=3)r2c7 - (3)r2c9 = (3)r6c9 - (3=6)r4c7 - loop => -9 r6c8, -3 r5c7; stte

Phil

[yzfwsf]

Because the composite structure composed of the two chains you found is not a zero rank structure, you cannot use Blossom Loop's elimination rule. Specifically, your first chain is a qualified burr ring, but the second chain is not a qualified burr branch, and the endpoint of the burr branch is a certain elimination of the burr ring.

You can use xsudo to verify the structure (although in most cases it cannot find the structure).

[pjb]

yzfwsf

Thank you for your reply. However, I'm still struggling. Can you tell me where I can find a clear definition of a "burr ring"? I've searched both this site and google without finding any helpful hits. Also "qualified" is something I would appreciate an explanation for.

Phil

[yzfwsf]

pjb

I don't know if you have seen this before？
http://forum.enjoysudoku.com/blossom-loop-t42270.html#p343083

And this chinese post:
https://tieba.baidu.com/p/7482719816