SudoCue Users

lac

This is working fine for me.

Laura

lac

Wonderful. Do you have an ISBN?

Laura Creighton

lac

I posted a couple of places that this was the place to find harder
Sudokus than 'Nordstedt's Sudoku Extreme' (a fairly popular
book of hard sudokus here). I have no idea if this has had any
effect, though.

Laura

lac

I've only placed r3c3 r1c5 r3c7 and r1c8.

Cannot see any swordfish, and gosh there are a lot of candidates left
everywhere ....

off to work, to will have to save this pleasure for lunchtime,

Laura

lac

Code: Select all


7..1.2..4
..36.92..
.1..4..8.
53.....62
..7...3..
12.....78
.4..6..2.
..94.18..
3..2.8..6

Interesting that the 6 placed in the bottom right house is not needed.
But it is a lot harder to solve without. But there is something else
interesting about this one, even with the 6 in.

Enjoy,
Laura

lac

hah! more than 1 way to skin this cat. I found 3 disjoing forcing chains.

Laura

lac

time to learn some new techniques, I guess.

Ruud, what ones do you need to solve this one?

Laura

lac

What I did was decide that the crucial question was 'Is r3c9' a 9. If if wasn't, then you could conclude r1c9 was 27or8. I first tried to get a contradiction by setting it to 9. no go. (unsurprising, that is what the solution was.) Then I set r3c3 to 9 (it would have to be ifr3c9 wasn't) and got a c...

lac

I really liked this one. I solved this with 3 separate colouring finds,
which my faulty memory thinks is tied for the record for Nightmares.

Thank you.

Laura

lac

I solved it the way David did -- and was also not satisfied. Plus it took
_hours_ ....

Laura, pleased to see a happier way

lac

I solved it, but it took a long time. Good for a change but not as much fun as a nightmare. I especially liked the symmettry. There is, however a problem in that one error can propegate widely. I misread my own writing, and took a 2 for a 3,with sad results, and had to start over once. Possibly maki...

lac

me i was rolling around on the floor laughing too.

Do I credit you to associating this particular ad, or parody with our
favourite passtime? or did somebody before you make the
connection?

In any case, thank you.

Laura

lac

Yes. meant r6c4. Sorry about that.

Laura

lac

Here is another way to solve this. Looking for placing of the 4s, you can prove that r5c6 can not be 4. If r2c4 is 4, then r8c4 must be 1, thus r8c6 is 4, and r5c6 is 4. But if r2c4 is not 4, then r2c9 must be 4, r3c8 must be 7 and r5c8 must be 4. Again, r5c4 cannot be 4, so it is 6. 4 268 26 68 1 7...

lac

I got to the same place where David started his double implication chain. And I too started with r1c1. But what I showed was that no matter which value you set r1c1 to, r4c3 must be 9. If 6, then r1c3 is 4, thus r4c3 is 9. If 9, then r5c1 is 7, r5c2 is 4¸ and again r4c3 is 9. This however, immediate...

SudoCue Users

Search found 43 matches

Thanks very much Pete

Extremely Nasty Sudoku

Popular in Sweden

you must be seeing something that I have not.

Here is another interesting one from Brain Bashers.

March 05 2003 nightmare

Yes that was a hard one.

Feb 24 2006 Nightmare

aha

back from business trip, look what I found

ruud, you silly man

typo, meant r6c4

Dec 24 nightmare

The many ways to solve the same puzzle: