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Almost Hidden XY-Ring (loop) Example

 
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Bud



Joined: 06 May 2010
Posts: 47
Location: Tampa, Florida

PostPosted: Fri Apr 22, 2011 1:12 pm    Post subject: Almost Hidden XY-Ring (loop) Example Reply with quote

000000200500800610100004000001690003007083900200047006005300008012008007006000000

After making basic moves the puzzle is as shown in the diagram below. The 4 cells in the almost hidden XY-Ring iare denoted by *. Note that a 2 conjugate is in column 2 of this pattern, a 7 conjugate is in row 2, a 6 conjugate is in row 3, and an almost 3 conjugate is in column 5. If this xy-ring is true, all other digits can be eliminated from these 4 cells. Note that this will occur if cell B<>3.
Next note the 23579 ALS with cells labeled A in box 2. This becomes a locked set 2579 if cell B=3. in either case r3c5<>257.
Also if B=3: (3)r1c5-r1c8=(3)r3c78, which implies that r3c2<>3.

Note that these eliminations are valid whether the xy-Ring is true or false.

Code:

+----------------------+-----------------------+------------------+
| 3679   3679     3489 | 579A   13567B    1569 | 2     378    459 |
| 5      2739*    349  | 8      237*A     29A  | 6     1      49  |
| 1      2-3679*  389  | 2579A  -23-56-7* 4    | 378   378    59  |
+----------------------+-----------------------+------------------+
| 48     458      1    | 6      9         25   | 457   2457   3   |
| 46     456      7    | 125    8         3    | 9     245    12  |
| 2      39       39   | 15     4         7    | 158   58     6   |
+----------------------+-----------------------+------------------+
| 479    479      5    | 3      1267      1269 | 14    2469   8   |
| 349    1        2    | 459    56        8    | 345   34569  7   |
| 34789  34789    6    | 24579  1257      1259 | 1345  23459  12  |
+----------------------+-----------------------+------------------+
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