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Tough Sudoku for 10/October/2006


Choose a number, and place it in the grid above.

  1 2 3 4 5 6 7 8 9
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Submitted by: sudoku lover

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What is Penny eating?
Penny looks like she would be a good 'watch' dog.
8:20 Maen
I'd give a penny for her. Dog lover here.
An interesting puzzle today. I'm sure there are shorter chains than the ones I used but I don't have time to look for them:

1) Start 22, Unique Possibilities to (UP) 27.
2) Naked pair 16 at hi2 forbids g2=16, g3=6, h1=16, a2=16, b2=1, d2=6, f2=6. UP 28.
3) Naked pair 16 at i25 More...
After two days TOUGH, I was waiting, but today...
Hi Penny ...!
Hi NICK from Toronto,
are you busy? I did not to see you 2 days on this Site, I always believe your timer then I can compare with my timer and I know that I solve tough good or not.
Hi Clark.
In your step 10)what happened to the 8 in d9 ? Did I miss something?
Possible proof of tough sudoku of 10 10 06:

1) Start at 22 filled - the given puzzle. Unique Possibilities to 27 filled. (UP 27).
2) Locked 5's at bc6 forbids efg6=5 UP 28
3) Pair 16 at i25 forbids i467=1 and forbids i469=6 UP 30
4) Pair 16 at hi2 forbids abg2h1=1 and forbids More...
In today's puzzle, there are so many,many paths available - I am certain that there is much to be improved upon from the poor excuse for a proof that I submitted. Mainly, I had trouble just decided which fc's to post, as there are quite a few depth 4 one's available. Perhaps there is a depth 4, or even a depth 3 proof possible - although such a proof will likely require some 'chunking'.
Hi kaz - I think that d9=9 after d8=1 in Clark's proof, thus eliminating that pesky 8.
Hello ttt. I was away camping. Got back yesterday but didn't have time to Sudoku (Thanksgiving dinner - Canadian holiday)

Good afternoon to all! Another cat???

Steve's answer to your question is correct. d9=9 after step 8.
To Clark & Steve. Okay, I need new glasses, how ever did I miss that 9??? It was sooo glaringly obvious! Thanks guys.
Penny dog - cheap at half the price!
Now THAT's a tail!
Penny out the front of our house when Leia was doing ochre painting (we found a rock we could make rock paint out of and made cave man hand and foot prints on the concrete patio). Schultz was out there too that day! All enjoying the fine weather - early Spring days!
Please see Outlander Discussion group update on Parent page.
I believe all the Outlander comments are what people are objecting to. What reason is there to put that comment on this page?
Dee, So that all who may be interested are informed. Its obvious that you aren't interested, so feel free to ignore the message. If however you want to see what all the fuss is about , perhaps you can join us and add whatever you wish to the comments at that time. We welcome one and all.
yes THATS a tail really.........and looks like penny has been helping in the painting too.....
a painter dog eh?
didnt time myself today..but good puzzle and enjoyed solving it..
one guess
Just realised this puzzle appeared on Penny's 1st birthday.
Oct. 17, 2007.
18/Oct/07 1:22 AM

05/Sep/10 10:10 PM
possible improvement:
1.SST to UP=31
2.kraken column(7)d139 => d3<>6,f1<>7 UP=54
3.(4=6)d4-d5=i5-(6=179)g367-(7=456)cde4 => c6<>6,d2<>4 STE.
15/Dec/10 3:15 AM
02/Feb/20 9:20 PM
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