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| Nick70
| Joined: 08 Jun 2005 | Posts: 160 | : | | Items |
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Posted: Sun Jul 10, 2005 3:05 pm Post subject: Naked quadruples |
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Problems that can be solved finding a quadruple seem to be very rare. Out of more than 30,000 that I have generated, there are a few examples of problems that allow use of naked quadruples, hidden quadruples, jellyfish to go ahead, but most of them cannot be completed without using more advanced techniques.
Here are the only two examples I have of problems that can be fully solved using quadruples.
Code: | ..8.9.7.6
.316.....
2........
.....5...
..9.1.3..
...4.....
........4
.....782.
7.6.3.1..
..7.9.8.5
.396.....
4........
.....5...
..6.1.3..
...4.....
........7
.....742.
8.3.6.1.. |
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| m_b_metcalf
| Joined: 13 Mar 2006 | Posts: 210 | : | Location: Berlin | Items |
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Posted: Wed Mar 15, 2006 2:32 pm Post subject: Re: Naked quadruples |
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Nick70 wrote: | Problems that can be solved finding a quadruple seem to be very rare. Out of more than 30,000 that I have generated, there are a few examples of problems that allow use of naked quadruples, hidden quadruples, jellyfish to go ahead, but most of them cannot be completed without using more advanced techniques.
Here are the only two examples I have of problems that can be fully solved using quadruples.
Code: | ..8.9.7.6
.316.....
2........
.....5...
..9.1.3..
...4.....
........4
.....782.
7.6.3.1.. |
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This is a very old posting but I've only just seen it. Neither my program nor I can identify the quadruple you refer to, at least in the first example. Could you please identify the cells and values concerned?
Thanks,
Mike Metcalf |
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| Ruud Site Admin
| Joined: 17 Sep 2005 | Posts: 708 | : | Location: Netherlands | Items |
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Posted: Wed Mar 15, 2006 3:03 pm Post subject: |
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Hi Mike,
I marked the cells with the first naked quad here:
Code: | .---------------------.---------------------.---------------------.
| 45 45 8 | 123 9 123 | 7 13 6 |
| 9 3 1 | 6 7 8 | 245 45 25 |
| 2 6 7 | 5 4 13 | 9 138 18 |
:---------------------+---------------------+---------------------:
| 13468 12478 234 | 39 28 5 |*24 14689 12789 |
| 458 2458 9 | 7 1 6 | 3 *458 *258 |
| 13568 12578 235 | 4 28 39 |*25 15689 125789|
:---------------------+---------------------+---------------------:
| 138 1289 23 | 1289 5 129 | 6 7 4 |
| 145 1459 45 | 19 6 7 | 8 2 3 |
| 7 28 6 | 28 3 4 | 1 59 59 |
'---------------------'---------------------'---------------------' |
And then a few reductions later here is the second, an exact mirror of the first:
Code: | .------------------.------------------.------------------.
| 45 45 8 | 123 9 123 | 7 13 6 |
| 9 3 1 | 6 7 8 | 245 45 25 |
| 2 6 7 | 5 4 13 | 9 138 18 |
:------------------+------------------+------------------:
| 13468 12478*234 | 39 28 5 | 24 169 179 |
|*45 *245 9 | 7 1 6 | 3 458 258 |
| 13568 12578*235 | 4 28 39 | 25 169 179 |
:------------------+------------------+------------------:
| 138 1289 23 | 1289 5 129 | 6 7 4 |
| 145 1459 45 | 19 6 7 | 8 2 3 |
| 7 28 6 | 28 3 4 | 1 59 59 |
'------------------'------------------'------------------' |
Ruud. _________________ Meet me at sudocue.net |
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| m_b_metcalf
| Joined: 13 Mar 2006 | Posts: 210 | : | Location: Berlin | Items |
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Posted: Wed Mar 15, 2006 7:15 pm Post subject: |
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Ruud,
Thanks, got it now.
Mike |
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