## To texlef, solution to your problem

Advanced methods and approaches for solving Sudoku puzzles

### To texlef, solution to your problem

The puzzle can be solved with two forcing chains:

1)

r3c1=1, -> r5c1=2, ->r5c3=3
r3c1=7, ->r3c2=8, ->r1c3=2, ->r5c3=3

2)

r4c1=7, ->r4c6=9, ->r5c5=6
r4c1=9, ->r6c2=7, ->r3c2=8, ->r3c6=6, ->r6c6=7,9 that forms a bare pair in square 5, eliminating the 9 from r5c5 so that r5c5=6

The puzzle falls apart fairly easily although I think (senior moments sometimes) that there may be one or two quads that need to be recognized. Hope this helps!
l\$

Posts: 2
Joined: 16 September 2005

This one goes with txlefs 'OK I Really Do Need Help Now' and I'd like to say that I think you've done a terrific job, 1\$, for a senior person, (and a cheap one too, by the looks!)
emm

Posts: 987
Joined: 02 July 2005

### Re: To texlef, solution to your problem

l\$ wrote:The puzzle can be solved with two forcing chains:

1)
r3c1=1, -> r5c1=2, ->r5c3=3
r3c1=7, ->r3c2=8, ->r1c3=2, ->r5c3=3

2)
r4c1=7, ->r4c6=9, ->r5c5=6
r4c1=9, ->r6c2=7, ->r3c2=8, ->r3c6=6, ->r6c6=7,9 that forms a bare pair in square 5, eliminating the 9 from r5c5 so that r5c5=6

Could you please list the grid at which these chains were forced? I couldn't follow your chain propagation logic. Thanks.
Jeff

Posts: 708
Joined: 01 August 2005