dailysudoku.com Forum Index dailysudoku.com
Discussion of Daily Sudoku puzzles
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Mandatory Pairs - Hard and Very Hard

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku puzzles
View previous topic :: View next topic  
Author Message
alanr555



Joined: 01 Aug 2005
Posts: 194
Location: Bideford Devon EX39

PostPosted: Mon Apr 17, 2006 11:05 pm    Post subject: Mandatory Pairs - Hard and Very Hard Reply with quote

Code:

For those practising use of Mandatory Pairs, the following list
may be of use. It includes the dates of Classic Daily Sudoku
puzzles which have been completely resolved using only the
Mandatory Pairs recording technique (ie it has not proved to
be necessary to derive candidate profiles at all). The puzzles
listed are in the Hard or Very Hard grades only.

As such these puzzles provide a challenge of solution without
resort to candidate profiles - knowing that it IS possible.

October 2005:  3,24,25.
November 2005: 4,8,17,27,28.
December 2005: 1,2,7,10,26.
January 2006: 2,3,5,6,8,15,20,24,25,26,28,31.
February 2006: 1,2,4,10,22,25.
March 2006: 9,10,11,15,17,25,31
April 2006: 1,3,8,11,15.

These puzzles can be retrieved quite simply from the Archive.

The other hard/veryhard puzzles cannot yet be claimed to be
solvable without resort to candidate profiles but research is
ongoing. In some cases the puzzles have been resolved with
resort only to writing down the "Missing Profiles" for all or
some of Rows or columns and so they may be considered as
being solved without candidates but they have not been
included in the list above.

Sadly human error (or just tiredness?!) can intervene - as often
missing just ONE pair can prevent a solution. Thus it is not yet
possible to state that those not listed cannot be resolved using
using just Mandatory Pairs techniques.

Alan Rayner  BS23 2QT
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Daily Sudoku puzzles All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group