Dan's deja-vu October 29, 2013

Post puzzles for others to solve here.

Dan's deja-vu October 29, 2013

Postby ArkieTech » Mon Oct 28, 2013 11:20 pm

From my collection. Source unknown.

Code: Select all
 *-----------*
 |7..|8.6|4..|
 |...|2..|...|
 |...|...|.3.|
 |---+---+---|
 |1..|...|..2|
 |...|5..|8..|
 |93.|...|...|
 |---+---+---|
 |.28|...|...|
 |...|.9.|.1.|
 |...|.3.|...|
 *-----------*


Play/Print this puzzle online
dan
User avatar
ArkieTech
 
Posts: 2823
Joined: 29 May 2006
Location: NW Arkansas USA

Re: Dan's deja-vu October 29, 2013

Postby pjb » Tue Oct 29, 2013 12:57 am

I went for the BUG-lite of 67's first: r2c89, r4c78, r9c79 => -4 r6c9, r7c8; giving:
Code: Select all
7      9      3      | 8      5      6      | 4      2      1     
8      5      14     | 2      14     3      | 9      67     67     
2      46     146    | 9      147    47     | 5      3      8     
---------------------+----------------------+---------------------
1      8      5      | 3     a67     9      |b67     4      2     
46     467    467    | 5      2      1      | 8      9      3     
9      3      2      | 467    8      47     | 1      5      67     
---------------------+----------------------+---------------------
46     2      8      | 1      47-6   5      | 3     d67     9     
3      467    467    | 46     9      8      | 2      1      5     
5      1      9      | 67     3      2      |c67     8      4     

(6=7) r4c5 - (7=6) r4c7 - (6=7) r9c7 - (7=6) r7c8 => -6 r7c5; stte

Phil
pjb
2014 Supporter
 
Posts: 1910
Joined: 11 September 2011
Location: Sydney, Australia

Re: Dan's deja-vu October 29, 2013

Postby Luke » Tue Oct 29, 2013 12:59 am

Hey, check this out, just for the hellavit. Because this puzzle is not *too* awful difficult, is anyone down for an added challenge?

Code: Select all
 *--------------------------------------------------*
 | 7    9    3    | 8    5    6    | 4    2    1    |
 | 8    5    14   | 2    14   3    | 9    67   67   |
 | 2    46   146  | 9    147  47   | 5    3    8    |
 |----------------+----------------+----------------|
 | 1    8    5    | 3    467  9    | 67   467  2    |
 | 46   467  467  | 5    2    1    | 8    9    3    |
 | 9    3    2    | 467  8    47   | 1    5    467  |
 |----------------+----------------+----------------|
 | 46   2    8    | 1    467  5    | 3    467  9    |
 | 3    467  467  | 46   9    8    | 2    1    5    |
 | 5    1    9    | 467  3    2    | 67   8    467  |
 *--------------------------------------------------*

This grid has more than one Type 1 deadly pattern. Find the one that reduces it to singles... :twisted:
User avatar
Luke
2015 Supporter
 
Posts: 435
Joined: 06 August 2006
Location: Southern Northern California

Re: Dan's deja-vu October 29, 2013

Postby daj95376 » Tue Oct 29, 2013 4:32 am

Code: Select all
 after basics
 +-----------------------------------------------------+
 |  7    9    3    |  8    5    6    |  4    2    1    |
 |  8    5    14   |  2    14   3    |  9   *67  *67   |
 |  2    46   146  |  9    147  47   |  5    3    8    |
 |-----------------+-----------------+-----------------|
 |  1    8    5    |  3   *67+4 9    | *67   467  2    |
 |  46   467  467  |  5    2    1    |  8    9    3    |
 |  9    3    2    | *67+4 8    47   |  1    5   *67+4 |
 |-----------------+-----------------+-----------------|
 |  46   2    8    |  1   *67+4 5    |  3   *67+4 9    |
 |  3    467  467  |  46   9    8    |  2    1    5    |
 |  5    1    9    | *67+4 3    2    | *67   8    467  |
 +-----------------------------------------------------+
 # 40 eliminations remain

While searching for Luke's DP, I found <67> in the (*) cells. Anything that forces this pattern must be false.

Code: Select all
4r6c6, 4r4c8, 4r9c9, 4r8c4; <67> DP  =>  r6c6<>4


A network using memory on eliminations for <4>:

Code: Select all
(7=14)r23c5 - (4)r47c5,r3c6 = r6c6 - r6c49 = r4c8 - r7c8 = r9c9 - r9c4; <67> DP  =>  r3c5=7
daj95376
2014 Supporter
 
Posts: 2624
Joined: 15 May 2006

Re: Dan's deja-vu October 29, 2013

Postby Leren » Tue Oct 29, 2013 6:51 am

Can't see a single DP move. (467) DP r358c23 => r3c3 <> 4,6 followed by an Avoidable Rectangle (14) r23c35 => r3c5 <> 4; stte

Leren
Leren
 
Posts: 3153
Joined: 03 June 2012

Re: Dan's deja-vu October 29, 2013

Postby Luke » Tue Oct 29, 2013 12:30 pm

Leren wrote:Can't see a single DP move.

Thanks for looking, Leren, but I think you did find the pattern. When DPs overlap like this they become a single pattern. They don't have to be the same type, any DPs can be mixed and matched. If that's too broad a statement, I'm open to discussion.

In this case the potential (467)MUG overlaps with the (14)AUR, creating a Muggur, shall we say.

Code: Select all
*--------------------------------------------------*
 | 7    9    3    | 8    5    6    | 4    2    1    |
 | 8    5   *14   | 2   *14   3    | 9    67   67   |
 | 2   *46  *146  | 9   *14+7 47   | 5    3    8    |
 |----------------+----------------+----------------|
 | 1    8    5    | 3    467  9    | 67   467  2    |
 | 46  *467 *467  | 5    2    1    | 8    9    3    |
 | 9    3    2    | 467  8    47   | 1    5    467  |
 |----------------+----------------+----------------|
 | 46   2    8    | 1    467  5    | 3    467  9    |
 | 3   *467 *467  | 46   9    8    | 2    1    5    |
 | 5    1    9    | 467  3    2    | 67   8    467  |
 *--------------------------------------------------*

The only out is 7(r3c5), and there's the Type 1 DP. Overlapping patterns can be more densely hidden, but still available for the strong inference sets that we commonly use for more conventional DPs. Why not, eh?
User avatar
Luke
2015 Supporter
 
Posts: 435
Joined: 06 August 2006
Location: Southern Northern California

Re: Dan's deja-vu October 29, 2013

Postby tlanglet » Tue Oct 29, 2013 1:36 pm

Luke,

I just looked at the puzzle for today and could not help but read all the posts after noting that you contributed. I doubt that I would have found the overlapping DPs in any case.

One comment. You solution is a Type 1 DP, r3c5=7, which is the "internal" strong inference. The only "external" strong inference is r3c6=4.

Ted
tlanglet
2010 Supporter
 
Posts: 538
Joined: 29 May 2010

Re: Dan's deja-vu October 29, 2013

Postby Marty R. » Tue Oct 29, 2013 3:09 pm

Code: Select all
+------------+------------+------------+
| 7  9   3   | 8   5   6  | 4  2   1   |
| 8  5   14  | 2   14  3  | 9  67  67  |
| 2  46  146 | 9   147 47 | 5  3   8   |
+------------+------------+------------+
| 1  8   5   | 3   467 9  | 67 467 2   |
| 46 467 467 | 5   2   1  | 8  9   3   |
| 9  3   2   | 467 8   47 | 1  5   467 |
+------------+------------+------------+
| 46 2   8   | 1   467 5  | 3  467 9   |
| 3  467 467 | 46  9   8  | 2  1   5   |
| 5  1   9   | 467 3   2  | 67 8   467 |
+------------+------------+------------+


I couldn't find the one-stepper. Too many 467s for me to process.

DP (67)r249c789 4r4c8=4r9c9=>r6c9,r7c8<>4

Code: Select all
+------------+------------+----------+
| 7  9   3   | 8   5   6  | 4  2  1  |
| 8  5   14  | 2   14  3  | 9  67 67 |
| 2  46  146 | 9   147 47 | 5  3  8  |
+------------+------------+----------+
| 1  8   5   | 3   67  9  | 67 4  2  |
| 46 467 467 | 5   2   1  | 8  9  3  |
| 9  3   2   | 467 8   47 | 1  5  67 |
+------------+------------+----------+
| 46 2   8   | 1   467 5  | 3  67 9  |
| 3  467 467 | 46  9   8  | 2  1  5  |
| 5  1   9   | 67  3   2  | 67 8  4  |
+------------+------------+----------+


Remote Pairs r9c4=67-r9c7=r4c7-r6c9=>r6c4<>67
Marty R.
 
Posts: 1508
Joined: 23 October 2012
Location: Rochester, New York, USA

Re: Dan's deja-vu October 29, 2013

Postby daj95376 » Tue Oct 29, 2013 4:13 pm

Marty, my solver didn't find a single-stepper. However, I did notice that my previous solution could be shortened.

Code: Select all
 after basics
 +-----------------------------------------------------+
 |  7    9    3    |  8    5    6    |  4    2    1    |
 |  8    5    14   |  2    14   3    |  9    67   67   |
 |  2    46   146  |  9    147  47   |  5    3    8    |
 |-----------------+-----------------+-----------------|
 |  1    8    5    |  3    467  9    | *67   467  2    |
 |  46   467  467  |  5    2    1    |  8    9    3    |
 |  9    3    2    | *67+4 8    47   |  1    5   *67+4 |
 |-----------------+-----------------+-----------------|
 |  46   2    8    |  1    467  5    |  3    467  9    |
 |  3    467  467  |  46   9    8    |  2    1    5    |
 |  5    1    9    | *67+4 3    2    | *67   8    467  |
 +-----------------------------------------------------+
 # 40 eliminations remain

A <67> oddagon in the (*) cells. Anything that forces this pattern must be false.

Code: Select all
(4): r8c4 - r69c4 = r9c9 - r6c9; <67> oddagon  =>  r8c4<>4
daj95376
2014 Supporter
 
Posts: 2624
Joined: 15 May 2006

Re: Dan's deja-vu October 29, 2013

Postby ArkieTech » Tue Oct 29, 2013 7:08 pm

Code: Select all
 *--------------------------------------------------*
 | 7    9    3    | 8    5    6    | 4    2    1    |
 | 8    5    14   | 2    14   3    | 9   *67  *67   |
 | 2    46   146  | 9    147  47   | 5    3    8    |
 |----------------+----------------+----------------|
 | 1    8    5    | 3    67-4 9    |*67  *4-67 2    |
 | 46   467  467  | 5    2    1    | 8    9    3    |
 | 9    3    2    | 467  8    47   | 1    5    467  |
 |----------------+----------------+----------------|
 | 46   2    8    | 1    4-67 5    | 3    467  9    |
 | 3    467  467  | 46   9    8    | 2    1    5    |
 | 5    1    9    | 467  3    2    |*67   8   *4-67 |
 *--------------------------------------------------*
bug lite *
=> -67r4c8,r7c5,r9c9 -4r6c9,r7c8; ste
dan
User avatar
ArkieTech
 
Posts: 2823
Joined: 29 May 2006
Location: NW Arkansas USA

Re: Dan's deja-vu October 29, 2013

Postby Leren » Tue Oct 29, 2013 9:32 pm

My default solving order found a Type 4 UR (14) r23c35 => r2c35 <> 4 followed immediately by the (467) DP r358c23 => r3c3 <> 6; stte

As there were no intervening eliminations between these 2 moves you might be able to claim that they are a single combined move ... maybe.
ArkieTech Wrote: bug lite * => -67r4c8,r7c5,r9c9 -4r6c9,r7c8; ste

Perhaps I don't understand enough about bug lites but the only direct elimination I can see from your 6 cell pattern is r6c9 <> 4 => r4c8, r9c9 <> 67, r4c5, r7c8, r9c4 <> 4. I can't see r7c5 <> 67. Could you explain ?

Leren
Leren
 
Posts: 3153
Joined: 03 June 2012

Re: Dan's deja-vu October 29, 2013

Postby ArkieTech » Wed Oct 30, 2013 1:38 am

Leren wrote: I can't see r7c5 <> 67. Could you explain ?


To break the 67 dp either 4r4c8 or 4r9c9 is needed. This results in r7c5 seeing two cells containing 67 extensions from the dp r7c8,r4c5 => -67r7c5 (a 16 skyscraper)

Hope this helps
dan
User avatar
ArkieTech
 
Posts: 2823
Joined: 29 May 2006
Location: NW Arkansas USA

Re: Dan's deja-vu October 29, 2013

Postby pjb » Wed Oct 30, 2013 2:06 am

Leren wrote:
My default solving order found a Type 4 UR (14) r23c35 => r2c35 <> 4 followed immediately by the (467) DP r358c23 => r3c3 <> 6; stte

By executing the Type 4 UR first, doesn't the removal of the 4 at r3c3 kill the MUG at r358c23?

ArkiTech wrote:
To break the 67 dp either 4r4c8 or 4r9c9 is needed. This results in r7c5 seeing two cells containing 67 extensions from the dp r7c8,r4c5 => -67r7c5 (a 16 skyscraper)

Using the Type 2 BUG-lite leads to the state in my post above. A skyscraper of 6 and then 7 removes 67 from r7c5, but isn't this a discrete second step rather than part of the BUG-lite?

Phil
pjb
2014 Supporter
 
Posts: 1910
Joined: 11 September 2011
Location: Sydney, Australia

Re: Dan's deja-vu October 29, 2013

Postby Leren » Wed Oct 30, 2013 6:29 am

pjb wrote: By executing the Type 4 UR first, doesn't the removal of the 4 at r3c3 kill the MUG at r358c23?

I don't see why it should ? The only requirement for the DP is that the six cells can't solve to just 3 digits 467 (with none of them being a given) and this must happen if
r3c3 = 6 so out it goes. In fact you could remove up to 8 candidates from r58c23 (without solving any of them) and the DP would still apply.

Leren
Leren
 
Posts: 3153
Joined: 03 June 2012


Return to Puzzles