Not sure if these are Remote Pairs

Post the puzzle or solving technique that's causing you trouble and someone will help

Not sure if these are Remote Pairs

Postby Audres » Thu Apr 17, 2014 1:38 pm

Hello, I'm a newbe to this forum and to sudoku and to posting in general.

My concern is that I encountered what could be Rremote Pairs of 1 and 6 in R9C35 and R8C58. The puzzle is from Andoku. When opened with Hoduku it reported an invalid puzzle. Sadman solved it placing a 3 in R7C8. My confusion is that it appears to consider R7C3 as part of the pairs, even if that cell has a 5 in it. I am also confused because I thought that remote pairs hat to be an even number. Sadmans solution appears to consider 5 Remote Pairs.

Any suggstion?
Audres
remote pairs.png
remote pairs.png (63.68 KiB) Viewed 1081 times
Audres
 
Posts: 2
Joined: 17 April 2014

Re: Not sure if these are Remote Pairs

Postby JasonLion » Thu Apr 17, 2014 6:23 pm

That is certainly a valid puzzle.

There isn't anything useful you can do with the Remote Pair you mention, at least using the simpler definition of remote pairs. However I have seen a more complex definition that incorporates ideas from unique rectangles. Using that more complex version there is an elimination that can be made. Using the Unique Rectangle type 4 principal combined with the four cells you mentioned, since R7C38 must contain 6, it can't contain 1. This pattern works with six cells, R9C35, R8C58, and R7C38.
User avatar
JasonLion
2017 Supporter
 
Posts: 642
Joined: 25 October 2007
Location: Silver Spring, MD, USA

Re: Not sure if these are Remote Pairs

Postby Audres » Fri Apr 18, 2014 12:22 am

Makes sense. Very helpful, thanks a lot.
Audres
 
Posts: 2
Joined: 17 April 2014

Re: Not sure if these are Remote Pairs

Postby Leren » Fri Apr 18, 2014 6:03 am

Hi Audres,

Your diagram shows that 8 can only go in Column 1 of Row 2, so you can immediately solve that cell.

Also in Row 9 there is a naked pair 16 in Columns 3 and 5, so you can remove the 1 from r9c1.

After that there is an XWing in 1's in Columns 1 and 9, Rows 3 and 7, which removes the 1 's from r7c3 and r7c8.

Finally there is a W Wing (23) in r1c9 and r2c2 linked by a pair of 2's in Column 3, which removes the 3's from r1c1 and r2c8.

Thereafter the puzzle solves by a cascade of singles.

Leren
Leren
 
Posts: 5040
Joined: 03 June 2012

Re: Not sure if these are Remote Pairs

Postby RyanStorm » Sun May 04, 2014 5:44 am

At bottom, you got them 1 or 6's across bottom row, well that means the bottom left 1, 3 or 7, you can erase the 1, because there will be a 1 or 6 in the other two. That doesn't add anything, but it narrows that down.
RyanStorm
 
Posts: 32
Joined: 04 May 2014


Return to Help with puzzles and solving techniques