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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Sun Nov 02, 2008 7:14 pm Post subject: No XY/XYZ-Wings: Set A Puzzle 9 |
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Same Rules! I don't think this puzzle is going to be cooperative at all
Code: | +-----------------------+
| 1 . . | 7 9 5 | . . . |
| . 2 . | 4 . . | . . 9 |
| . . . | . 2 . | . . . |
|-------+-------+-------|
| 8 1 . | . 3 7 | . 4 . |
| 4 . 2 | 1 6 . | 7 . . |
| 3 . . | 2 . 4 | . . 1 |
|-------+-------+-------|
| . . . | . 7 . | . . 2 |
| . . . | 3 . . | . 5 7 |
| . 3 . | . . 2 | 4 9 8 |
+-----------------------+
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Sun Nov 02, 2008 8:05 pm Post subject: |
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Quote: | An M-wing takes you a long way. I am still looking for a final step that Asellus will not complain about. |
Keith |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Sun Nov 02, 2008 8:17 pm Post subject: |
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Code: | .---------------------------.---------------------------.---------------------------.
| 1 468 3468 | 7 9 5 | 368 2 346 |
| 567 2 35678 | 4 18 1368 | 13568 1367 9 |
| 5679 456789 3456789 | 68 2 1368 | 13568 1367 346 |
:---------------------------+---------------------------+---------------------------:
| 8 1 569 | 59 3 7 | 2 4 56 |
| 4 59 2 | 1 6 89 | 7 38 35 |
| 3 567 567 | 2 58 4 | 9 68 1 |
:---------------------------+---------------------------+---------------------------:
| 569 45689 145689 | 5689 7 1689 | 136 136 2 |
| 2 689 1689 | 3 4 1689 | 16 5 7 |
| 567 3 1567 | 56 15 2 | 4 9 8 |
'---------------------------'---------------------------'---------------------------' |
I am just amazed at the 7 candidates left in r3c3 |
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Sun Nov 02, 2008 8:56 pm Post subject: |
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Norm,
In your grid there is an M-wing Quote: | 58 - 59 - 89 - 59 that solves R6C5 as <5>. (It eliminates <5> in R6C23.) |
Keith |
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Sun Nov 02, 2008 9:21 pm Post subject: |
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After the M-wing, I get to here:
Code: | +-------------+-------------+-------------+
| 1 46 4-8 | 7 9 5 | 68a 2 3 |
| 567 2 3 | 4 8 1 | 56 67 9 |
| 579 57 89d | 6 2 3 |15-8 17 4 |
+-------------+-------------+-------------+
| 8 1 5 | 9 3 7 | 2 4 6 |
| 4 9 2 | 1 6 8 | 7 3 5 |
| 3 67 67 | 2 5 4 | 9 8 1 |
+-------------+-------------+-------------+
| 59 45 149 | 8 7 69 | 3 16 2 |
| 2 8 19c | 3 4 69 | 16b 5 7 |
| 67 3 67 | 5 1 2 | 4 9 8 |
+-------------+-------------+-------------+ |
The XY-chain abcd has pincers <8>, making the eliminations shown. Done.
Keith |
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storm_norm
Joined: 18 Oct 2007 Posts: 1741
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Posted: Sun Nov 02, 2008 9:24 pm Post subject: |
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keith wrote: | Norm,
In your grid there is an M-wing Quote: | 58 - 59 - 89 - 59 that solves R6C5 as <5>. (It eliminates <5> in R6C23.) |
Keith |
hi keith, I was posting the grid for those who might not have the grid after basics and yes, I see the m-wing and there is a w-wing
the w-wing has the strong link on 5 in col 9.
both will take you a long way. the next move will have to involve stringing together some of those bi-value cells (xy-chains). |
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Asellus
Joined: 05 Jun 2007 Posts: 865 Location: Sonoma County, CA, USA
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Posted: Sun Nov 02, 2008 10:33 pm Post subject: |
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Keith,
To me, your M-Wing looks like an XY-Wing with a moustache again. |
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Sun Nov 02, 2008 10:38 pm Post subject: |
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In all of my No puzzles so far, XY-Chains were available to crack the puzzles ... but were never used. Interesting that this puzzle could be reduced to 27 eliminations remaining ... and still present a problem if XY/XYZ-Wings are removed from the solving techniques. |
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Sun Nov 02, 2008 11:04 pm Post subject: |
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I can't get keith's M-Wing to work. So I'll supply an alternate.
Code: | M-Wing: 59-89-59-35 => [r4c9]<>5
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Asellus
Joined: 05 Jun 2007 Posts: 865 Location: Sonoma County, CA, USA
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Posted: Sun Nov 02, 2008 11:04 pm Post subject: |
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After Norm's W-Wing, an XY chain can be avoided by, for example:
(5-8)r3c7=(8)r1c7 - (8=4)r1c3 - (4)r1c2=(4-5)r7c2=(5)r3c2 - (5)r3c7; r3c7<>5
This is basically a Medusa Trap. After this, there is a BUG+1.
Perhaps the avoidance of XY chains is because they are too much like "extended" XY Wings. |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Mon Nov 03, 2008 1:55 am Post subject: |
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After five assorted moves, I got stuck here:
Code: |
+------------+--------+----------+
| 1 46 48 | 7 9 5 | 68 2 3 |
| 567 2 3 | 4 8 1 | 56 67 9 |
| 79 57 89 | 6 2 3 | 158 17 4 |
+------------+--------+----------+
| 8 1 5 | 9 3 7 | 2 4 6 |
| 4 9 2 | 1 6 8 | 7 3 5 |
| 3 67 67 | 2 5 4 | 9 8 1 |
+------------+--------+----------+
| 59 45 149 | 8 7 69 | 3 16 2 |
| 2 8 19 | 3 4 69 | 16 5 7 |
| 67 3 67 | 5 1 2 | 4 9 8 |
+------------+--------+----------+
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Play this puzzle online at the Daily Sudoku site
At this point it easily succumbs to a Medusa wrap, but I would've been happier with something else. |
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Mon Nov 03, 2008 3:19 am Post subject: |
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Asellus wrote: | Keith,
To me, your M-Wing looks like an XY-Wing with a moustache again. |
And, how is that? |
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Mon Nov 03, 2008 3:30 am Post subject: |
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daj95376 wrote: | I can't get keith's M-Wing to work. |
Why not?
Norm's grid: Code: | .---------------------------.---------------------------.---------------------------.
| 1 468 3468 | 7 9 5 | 368 2 346 |
| 567 2 35678 | 4 18 1368 | 13568 1367 9 |
| 5679 456789 3456789 | 68 2 1368 | 13568 1367 346 |
:---------------------------+---------------------------+---------------------------:
| 8 1 569 | 59c 3 7 | 2 4 56 |
| 4 59a 2 | 1 6 89b | 7 38 35 |
| 3 -567 -567 | 2 58d 4 | 9 68 1 |
:---------------------------+---------------------------+---------------------------:
| 569 45689 145689 | 5689 7 1689 | 136 136 2 |
| 2 689 1689 | 3 4 1689 | 16 5 7 |
| 567 3 1567 | 56 15 2 | 4 9 8 |
'---------------------------'---------------------------'---------------------------' |
a and c have the same value. Strong links on <9>. Extending from c to d with a strong link on <5>, Pincers are <5> in a and d, making the eliminations shown. Leaving d as the only <5> in R6.
Last edited by keith on Mon Nov 03, 2008 3:48 am; edited 1 time in total |
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Mon Nov 03, 2008 3:43 am Post subject: |
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keith wrote: | After the M-wing, I get to here:
Code: | +-------------+-------------+-------------+
| 1 46 4-8 | 7 9 5 | 68a 2 3 |
| 567 2 3 | 4 8 1 | 56 67 9 |
| 579 57 89d | 6 2 3 |15-8 17 4 |
+-------------+-------------+-------------+
| 8 1 5 | 9 3 7 | 2 4 6 |
| 4 9 2 | 1 6 8 | 7 3 5 |
| 3 67 67 | 2 5 4 | 9 8 1 |
+-------------+-------------+-------------+
| 59 45 149 | 8 7 69 | 3 16 2 |
| 2 8 19c | 3 4 69 | 16b 5 7 |
| 67 3 67 | 5 1 2 | 4 9 8 |
+-------------+-------------+-------------+ |
The XY-chain abcd has pincers <8>, making the eliminations shown. Done.
Keith |
And, Asellus, if you are complaining about this move: There are no XY-wings in this grid. There is an XYZ-wing, far removed from my elimination.
I can give you a 10-link chain in this grid that makes an elimination, if you think that more satisfies your intellect?
Keith |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Mon Nov 03, 2008 4:52 am Post subject: |
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keith wrote: | daj95376 wrote: | I can't get keith's M-Wing to work. |
Why not?
Norm's grid: Code: | .---------------------------.---------------------------.---------------------------.
| 1 468 3468 | 7 9 5 | 368 2 346 |
| 567 2 35678 | 4 18 1368 | 13568 1367 9 |
| 5679 456789 3456789 | 68 2 1368 | 13568 1367 346 |
:---------------------------+---------------------------+---------------------------:
| 8 1 569 | 59c 3 7 | 2 4 56 |
| 4 59a 2 | 1 6 89b | 7 38 35 |
| 3 -567 -567 | 2 58d 4 | 9 68 1 |
:---------------------------+---------------------------+---------------------------:
| 569 45689 145689 | 5689 7 1689 | 136 136 2 |
| 2 689 1689 | 3 4 1689 | 16 5 7 |
| 567 3 1567 | 56 15 2 | 4 9 8 |
'---------------------------'---------------------------'---------------------------' |
a and c have the same value. Strong links on <9>. Extending from c to d with a strong link on <5>, Pincers are <5> in a and d, making the eliminations shown. Leaving d as the only <5> in R6. |
It's also a W-Wing connected by the 5s in row 6. |
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keith
Joined: 19 Sep 2005 Posts: 3355 Location: near Detroit, Michigan, USA
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Posted: Mon Nov 03, 2008 5:02 am Post subject: |
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It's also a W-Wing connected by the 5s in row 6.
There is not a strong link on <5> in R6. Am I missing something, like grouped coloring?
Keith |
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Marty R.
Joined: 12 Feb 2006 Posts: 5770 Location: Rochester, NY, USA
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Posted: Mon Nov 03, 2008 5:23 am Post subject: |
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keith wrote: | It's also a W-Wing connected by the 5s in row 6.
There is not a strong link on <5> in R6. Am I missing something, like grouped coloring?
Keith |
The way it was explained to me a year or so ago is that the 5 in row 6 is in either column 5 or box 1, ergo, the connection.
If this is grouped coloring or grouped strong links and I'm explaining it to you, then something's seriously wrong in this world!! |
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Asellus
Joined: 05 Jun 2007 Posts: 865 Location: Sonoma County, CA, USA
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Posted: Mon Nov 03, 2008 7:18 am Post subject: |
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Yes, that is a grouped strong link on <5> in r6 and it activate's the 59 W-Wing Norm already pointed out. You could also use the strong link on <5> in c9 to do so. But, that W-Wing is not Keith's M-Wing.
Keith wrote: | And, Asellus, if you are complaining about this move: There are no XY-wings in this grid. There is an XYZ-wing, far removed from my elimination.
I can give you a 10-link chain in this grid that makes an elimination, if you think that more satisfies your intellect? |
I have no complaints about XY chains. Danny just mentioned that no one was using them and I suggested why they might be avoiding them. I prefer to try Medusa coloring over looking for XY chains. But, that's just me.
As for that first M-Wing, it performs exactly the same eliminations as, and includes all of the cells of, the XY-Wing in r5c26|r6c5. But, it IS an M-Wing (I can see it even if some others can't). Myself, I would reject using it, per Danny's challenge, since it is too close to the prohibited XY Wing. However I'm certainly not making the rules for these puzzles: Danny is. So, he can judge. It is a matter of indifference to me. And, it has nothing whatsoever to do with intellect! |
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Asellus
Joined: 05 Jun 2007 Posts: 865 Location: Sonoma County, CA, USA
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Posted: Mon Nov 03, 2008 7:30 am Post subject: |
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P.S.:
Just to show that I am not being arbitrary, take a look at the thread for "Set A Puzzle 1". nataraj used a generalized M-Wing that includes XY-Wing cells and performs the same elimination, just as the case here. And, it is Danny who objects, not me. |
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daj95376
Joined: 23 Aug 2008 Posts: 3854
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Posted: Mon Nov 03, 2008 6:30 pm Post subject: |
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keith wrote: | Why not?
Norm's grid: Code: | .---------------------------.---------------------------.---------------------------.
| 1 468 3468 | 7 9 5 | 368 2 346 |
| 567 2 35678 | 4 18 1368 | 13568 1367 9 |
| 5679 456789 3456789 | 68 2 1368 | 13568 1367 346 |
:---------------------------+---------------------------+---------------------------:
| 8 1 569 | 59c 3 7 | 2 4 56 |
| 4 59a 2 | 1 6 89b | 7 38 35 |
| 3 -567 -567 | 2 58d 4 | 9 68 1 |
:---------------------------+---------------------------+---------------------------:
| 569 45689 145689 | 5689 7 1689 | 136 136 2 |
| 2 689 1689 | 3 4 1689 | 16 5 7 |
| 567 3 1567 | 56 15 2 | 4 9 8 |
'---------------------------'---------------------------'---------------------------' |
a and c have the same value. Strong links on <9>. Extending from c to d with a strong link on <5>, Pincers are <5> in a and d, making the eliminations shown. Leaving d as the only <5> in R6. |
This is your hint to Norm for the M-Wing.
Code: | 58 - 59 - 89 - 59 that solves R6C5 as <5>. (It eliminates <5> in R6C23.)
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I tried to make an M-Wing out of your cells ... in the order you provided them! Later, I did manage to reverse the cell order and find your M-Wing.
BTW: In this grid, there is an XY-Wing (59a-98b-85d) that uses three of your four cells and performs the same eliminations as your M-Wing. Not a good choice given the theme of the No puzzles. |
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