## Typo in Augusta Chronicle 27 Dec 2008?

All about puzzles in newspapers, magazines, and books
udosuk (on Sat Dec 27, 2008 6:34 pm) wrote:But you don't need that little cycle - only the XY-chain is required:

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`+-------------------+-------------------+-------------------+| 189   6     3     | 2     189   19    | 57   *57    4     || 1589  58    4     | 7     189   6     | 3     2     18    || 18    7     2     | 3     5     4     | 9     18    6     |+-------------------+-------------------+-------------------+| 78    38    6     | 5     379   2     | 4     18    189   || 578   2     1     | 4     36    79    | 57    36    89    || 4     35    9     | 1    *67    8     | 2    *67    35    |+-------------------+-------------------+-------------------+| 2     1     5     | 8     4     3     | 6     9     7     || 6     4     7     | 9     12    15    | 8     3-5   235   || 3     9     8     | 6    *27    57    | 1     4    *25    |+-------------------+-------------------+-------------------+`

r1c8+r6c58+r9c59 can't be [77622] => r8c8 can't be 5

On the other hand, I don't like chains so this might be how I crack it...

There is also a very short forcing chain (darn near an XY-wing ... maybe it is a wing of some sort -- I am unsure as I haven't really learned the more advanced wings) that cracks it to singletons (assuming I grabbed the right PM's as a starting point):
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`189  6  3 | 2 189 19 | 57 57 4  1589 58 4 | 7 189 6  | 3  2  18 18   7  2 | 3 5   4  | 9  18 6  ----------+----------+----------78   38 6 | 5 379 2  | 4  18 189578  2  1 | 4 36  79 | 57 36 89 4    35 9 | 1 67  8  | 2  67 35 ----------+----------+----------2    1  5 | 8 4   3  | 6  9  7  6    4  7 | 9 12  15 | 8  35 2353    9  8 | 6 27  57 | 1  4  25 r5c6=7 r5c7=5 + r9c6=7 r9c9=5 ==> r6c9<>5`

Cheers...

- drac

[edit: removed spurrious reference to c9]
Draco

Posts: 143
Joined: 14 March 2008

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