| View previous topic :: View next topic |
| Author |
Message |
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
 Posted: Mon Jul 12, 2010 2:15 pm Post subject: Puzzle 10/07/12: Extreme |
 |
|
| Code: | +-----------------------+
| 2 6 . | 5 . . | . . . |
| 5 . . | 6 4 . | . 2 . |
| . . 4 | . . . | . 6 . |
|-------+-------+-------|
| 1 3 . | 2 . . | . 4 . |
| . 7 . | . 1 3 | 9 5 2 |
| . . . | . 7 6 | . . . |
|-------+-------+-------|
| . . . | . 2 . | 3 7 . |
| . 1 2 | 7 6 . | 5 8 . |
| . . . | . 5 . | . . 6 |
+-----------------------+
|
Play this puzzle online at the Daily Sudoku site
| Code: | after basics
+--------------------------------------------------------------+
| 2 6 13 | 5 89 7 | 4 139 1389 |
| 5 89 13 | 6 4 189 | 7 2 1389 |
| 7 89 4 | 189 3 2 | 18 6 5 |
|--------------------+--------------------+--------------------|
| 1 3 89 | 2 89 5 | 6 4 7 |
| 468 7 68 | 48 1 3 | 9 5 2 |
| 49 2 5 | 49 7 6 | 18 13 138 |
|--------------------+--------------------+--------------------|
| 689 5 689 | 189 2 1489 | 3 7 149 |
| 3 1 2 | 7 6 49 | 5 8 49 |
| 89 4 7 | 3 5 189 | 2 19 6 |
+--------------------------------------------------------------+
# 47 eliminations remain
|
|
|
| Back to top |
|
 |
Mogulmeister
Joined: 03 May 2007
Posts: 1151
|
| Posted: Mon Jul 12, 2010 3:27 pm Post subject: |
|
|
A two step to start with:
| Quote: | 1.Colouring on 1s* r6c8<>1
2.XY Wing <189> vertex at r3c8; r1c9<>8 solves puzzle |
[Ed]Correction !!
Last edited by Mogulmeister on Mon Jul 12, 2010 4:42 pm; edited 1 time in total |
|
| Back to top |
|
|
Mogulmeister
Joined: 03 May 2007
Posts: 1151
|
| Posted: Mon Jul 12, 2010 4:09 pm Post subject: |
|
|
| Quote: | OK an almost XY wing (asterisks) <189> which has a fin (3) in r1c8
IF FIN false then r1c9, r3c4<>8 solves puzzle
otherwise
FIN true (19=3)r1c8-(3=1)r6c8-(1)r6c7; r6c7<>1 solves puzzle
|
| Code: | +----------------+----------------+----------------+
| 2 6 13 | 5 *89 7 | 4 *139 139-8 |
| 5 89 13 | 6 4 189 | 7 2 1389 |
| 7 89 4 | 19-8 3 2 |*18 6 5 |
+----------------+----------------+----------------+
| 1 3 89 | 2 89 5 | 6 4 7 |
| 468 7 68 | 48 1 3 | 9 5 2 |
| 49 2 5 | 49 7 6 |8-1 13 138 |
+----------------+----------------+----------------+
| 689 5 689 | 189 2 1489 | 3 7 149 |
| 3 1 2 | 7 6 49 | 5 8 49 |
| 89 4 7 | 3 5 189 | 2 19 6 |
+----------------+----------------+----------------+ |
|
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Tue Jul 13, 2010 3:47 am Post subject: |
|
|
My first pass was two steps........
| Quote: | ER9 with hinge box7 SL r6c14: r7c4<>9
Flightless w-wing 18 r6c7 & r7c4 SL (1)r3c47 plus transport (8)r7c4-r79c6=r2c6-r1c5=(8)r1c9; r6c9<>8
|
Ted |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Tue Jul 13, 2010 3:59 am Post subject: |
|
|
| Mogulmeister wrote: | | Quote: | OK an almost XY wing (asterisks) <189> which has a fin (3) in r1c8
IF FIN false then r1c9, r3c4<>8 solves puzzle
otherwise
FIN true (19=3)r1c8-(3=1)r6c8-(1)r6c7; r6c7<>1 solves puzzle
|
| Code: | +----------------+----------------+----------------+
| 2 6 13 | 5 *89 7 | 4 *139 139-8 |
| 5 89 13 | 6 4 189 | 7 2 1389 |
| 7 89 4 | 19-8 3 2 |*18 6 5 |
+----------------+----------------+----------------+
| 1 3 89 | 2 89 5 | 6 4 7 |
| 468 7 68 | 48 1 3 | 9 5 2 |
| 49 2 5 | 49 7 6 |8-1 13 138 |
+----------------+----------------+----------------+
| 689 5 689 | 189 2 1489 | 3 7 149 |
| 3 1 2 | 7 6 49 | 5 8 49 |
| 89 4 7 | 3 5 189 | 2 19 6 |
+----------------+----------------+----------------+ |
|
MM,
This is the second time I have noticed a post by you where you solve a finned step by noting that both the step and the fin complete the puzzle. Do you actually follow the implications of both to determine what happens, or do you use some Mogul Magic. I love the scheme, but the task of analyzing each implication of the fin seems to be overwhelming.
Ted |
|
| Back to top |
|
|
Mogulmeister
Joined: 03 May 2007
Posts: 1151
|
| Posted: Tue Jul 13, 2010 7:02 am Post subject: |
|
|
Ted, I generally look to see what Almost structures (ALS xy, ANx, AHP, ALS, XY, XYZ) could be lurking in the puzzle - this is the most entertaining part for me.
I then look to see if, when unencumbered, those structures do serious damage to the puzzle - quite often they are unproductive or just a step along the way. If they show promise, I will then see what happens to any fin.
Ideally they will loop back to make a virtuous circle but oftimes do not! This is why in some of my schemes the fin sometimes makes the same elimination (as in your kraken) but is not a given.
I create several als to look at implications as I enjoy these - I find it quite rewarding as it brings in pattern and chain recognition into the solving mindset. As to overwhelming - I find that you do develop an instinct/hunch. |
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Tue Jul 13, 2010 12:01 pm Post subject: |
|
|
| UR (13) boxes13; r12c9<>9 |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Tue Jul 13, 2010 2:00 pm Post subject: |
|
|
| Mogulmeister wrote: | Ted, I generally look to see what Almost structures (ALS xy, ANx, AHP, ALS, XY, XYZ) could be lurking in the puzzle - this is the most entertaining part for me.
I then look to see if, when unencumbered, those structures do serious damage to the puzzle - quite often they are unproductive or just a step along the way. If they show promise, I will then see what happens to any fin.
Ideally they will loop back to make a virtuous circle but oftimes do not! This is why in some of my schemes the fin sometimes makes the same elimination (as in your kraken) but is not a given.
I create several als to look at implications as I enjoy these - I find it quite rewarding as it brings in pattern and chain recognition into the solving mindset. As to overwhelming - I find that you do develop an instinct/hunch. |
MM, I share your enjoyment of looking for "almost" patterns and then checking out the possibilities. Such an approach offers an unlimited set of possible patterns to consider whereas searching for only "classic" patterns may become routine. Plus, as you indicated, chasing the implications can be extremely challenging but fun.
Ted |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Tue Jul 13, 2010 3:21 pm Post subject: |
|
|
I'm still working on Marty's solution. In the meantime, my solver found a short network that I was able to convert.
This is just a FYI:
| Code: | (89=1)r2c26 - r9c6 = (1-9)r9c8 = (9)r1c8 => r2c9<>9
|
Anyone get anywhere examining the overlapping <13> URs ?
Last edited by daj95376 on Tue Jul 13, 2010 3:23 pm; edited 1 time in total |
|
| Back to top |
|
|
Mogulmeister
Joined: 03 May 2007
Posts: 1151
|
| Posted: Tue Jul 13, 2010 3:23 pm Post subject: |
|
|
| Yes please elucidate Danny/Marty on that UR 13 solution - I'm not the greatest UR practitioner (as you can tell from my solutions)! |
|
| Back to top |
|
|
Mogulmeister
Joined: 03 May 2007
Posts: 1151
|
| Posted: Tue Jul 13, 2010 3:29 pm Post subject: |
|
|
| daj95376 wrote: | I'm still working on Marty's solution. In the meantime, my solver found a short network that I was able to convert.
This is just a FYI:
| Code: | (89=1)r2c26 - r9c6 = (1-9)r9c8 = (9)r1c8 => r2c9<>9
|
Anyone get anywhere examining the overlapping <13> URs ? |
Danny, presumably you mean (9)r1c8 => r12c9<>9 |
|
| Back to top |
|
|
Mogulmeister
Joined: 03 May 2007
Posts: 1151
|
| Posted: Tue Jul 13, 2010 3:33 pm Post subject: |
|
|
| Sorry, by mean I meant need. |
|
| Back to top |
|
|
Marty R.
Joined: 12 Feb 2006
Posts: 5770
Location: Rochester, NY, USA
|
| Posted: Tue Jul 13, 2010 3:50 pm Post subject: |
|
|
| When I was looking at the implications, a 9 in r12c9 led to an invalidity. I certainly could have erred, but I did check twice to make sure. |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Tue Jul 13, 2010 5:05 pm Post subject: |
|
|
| Mogulmeister wrote: | | daj95376 wrote: | I'm still working on Marty's solution. In the meantime, my solver found a short network that I was able to convert.
This is just a FYI:
| Code: | (89=1)r2c26 - r9c6 = (1-9)r9c8 = (9)r1c8 => r2c9<>9
|
Anyone get anywhere examining the overlapping <13> URs ? |
Danny, presumably you mean (9)r1c8 => r12c9<>9 |
The <89> pair starting my chain only has peers in [r2]. Thus, the single elimination. Resulting in:
| Code: | r1 b3 Locked Candidate 1 <> 9 r1c5
Singles to End (STE)
|
Last edited by daj95376 on Tue Jul 13, 2010 5:48 pm; edited 2 times in total |
|
| Back to top |
|
|
tlanglet
Joined: 17 Oct 2007
Posts: 2468
Location: Northern California Foothills
|
| Posted: Tue Jul 13, 2010 5:22 pm Post subject: |
|
|
| daj95376 wrote: | I'm still working on Marty's solution. In the meantime, my solver found a short network that I was able to convert.
This is just a FYI:
| Code: | (89=1)r2c26 - r9c6 = (1-9)r9c8 = (9)r1c8 => r2c9<>9
|
Anyone get anywhere examining the overlapping <13> URs ? |
Yes, I looked at both the overlapping URs and the 6-cell DP r126c689 but the only thing I found was the deletion r2c9<>9
as you noted.
Ted |
|
| Back to top |
|
|
daj95376
Joined: 23 Aug 2008
Posts: 3854
|
| Posted: Tue Jul 13, 2010 5:46 pm Post subject: |
|
|
My solver found the following UR eliminations:
| Code: | +--------------------------------------------------------------+
| 2 6 13 | 5 89 7 | 4 139 1389 |
| 5 89 13 | 6 4 189 | 7 2 1389 |
| 7 89 4 | 189 3 2 | 18 6 5 |
|--------------------+--------------------+--------------------|
| 1 3 89 | 2 89 5 | 6 4 7 |
| 468 7 68 | 48 1 3 | 9 5 2 |
| 49 2 5 | 49 7 6 | 18 13 138 |
|--------------------+--------------------+--------------------|
| 689 5 689 | 189 2 1489 | 3 7 149 |
| 3 1 2 | 7 6 49 | 5 8 49 |
| 89 4 7 | 3 5 189 | 2 19 6 |
+--------------------------------------------------------------+
# 47 eliminations remain
r78c69 <49> UR Type 4.2243 r7c69<>9
<x list-only>
r57c13 <68> UR via s-link <> 8 r5c1
r57c13 <68> UR via s-link <> 8 r7c1
r57c13 <68> UR via s-link <> 8 r7c3
r12c39 <13> UR via s-link <> 1 r1c9
r78c69 <49> UR via s-link <> 9 r7c6 same as Type 4 above
r78c69 <49> UR via s-link <> 9 r7c9 same as Type 4 above
<s list-only>
|
After Marty mentioned his eliminations on 9s, I examined the <13> UR and found two eliminations (that didn't help).
| Code: | ( r1c9=8 | r2c9=8 ) r3c7=1 => r12c9<>1
( r1c9=9 | r2c9=9 ) r8c9=4 r7c9=1 => r12c9<>1
|
Marty's used of an invalidity based on r12c9=9 explains why I couldn't duplicate his eliminations. |
|
| Back to top |
|
|
|
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
