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feb 24 bundle
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Victor



Joined: 29 Sep 2005
Posts: 207
Location: NI
PostPosted: Mon Feb 25, 2008 8:30 pm    Post subject: Reply with quote
Splendid stuff, Steve, explained in your usual laconic style! As always, I think Why didn't I see that ? - never do.
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Myth Jellies



Joined: 27 Jun 2006
Posts: 64
PostPosted: Tue Feb 26, 2008 7:23 am    Post subject: Reply with quote
ravel wrote:
...leaves an interesting BUG+3 situation:
Code:
+--------------------------+--------------------------+--------------------------+
| 3         8         6    | 5          4       7     | 9          2        1    |
| 59        7         15   | 2          3       19    | 8          6        4    |
| 4         19        2    | 16+8       69+8    18    | 3          7        5    |
+--------------------------+--------------------------+--------------------------+
| 59        2         7    | 3          1       59    | 4          8        6    |
| 6         19        15   | 48         89      458   | 2          3        7    |
| 8         4         3    | 7          2       6     | 5          1        9    |
+--------------------------+--------------------------+--------------------------+
| 27        3         9    | 46         67      24    | 1          5        8    |
| 17        5         4    | 18         78      3     | 6          9        2    |
| 12        6         8    | 9          5       12    | 7          4        3    |
+--------------------------+--------------------------+--------------------------+
Though there are only two 8's in column 6, an 8 in r3c6 would lead to a deadly BUG pattern.


Another way of looking at this is as a giant BUG-Lite+3....
Code:
+--------------------------+--------------------------+--------------------------+
| 3         8         6    | 5          4       7     | 9          2        1    |
|*59        7        *15   | 2          3      *19    | 8          6        4    |
| 4        *19        2    |*16+8      *69+8    18    | 3          7        5    |
+--------------------------+--------------------------+--------------------------+
|*59        2         7    | 3          1      *59    | 4          8        6    |
| 6        *19       *15   |*48        *89     *45+8  | 2          3        7    |
| 8         4         3    | 7          2       6     | 5          1        9    |
+--------------------------+--------------------------+--------------------------+
|*27        3         9    |*46        *67     *24    | 1          5        8    |
|*17        5         4    |*18        *78      3     | 6          9        2    |
|*12        6         8    | 9          5      *12    | 7          4        3    |
+--------------------------+--------------------------+--------------------------+

The only unsolved cell that isn't part of this BUG-Lite is r3c6. Obviously, the BUG-Lite shows that r3c6 <> 8. Often times, when you can almost, but not quite come up with a BUG, you can make a giant BUG-Lite.
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ravel



Joined: 21 Apr 2006
Posts: 536
PostPosted: Tue Feb 26, 2008 9:52 am    Post subject: Reply with quote
Of course this nice BUG-Lite is a bit hard to spot.
I only noticed it, when i looked, what the effect of r3c6=8 would be. It can be verified rather quickly then, that each number would occur exactly two times in all units, where it is contained in bivalue cells.
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