Sudoku Puzzles

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8:32 good Maen all. interesting architecture!

28:44

12:11....Only OK...got interrupted 5 times. Lost my train of thought.

today I'm the first. Very strange picture. In any case, I like pearls

Good Maen to all. Now I feel guilty. It's Sunday morning here and I didn't go to church. Hey wait a minute... the church just came to me when I finished the puzzle. Does that count??

Just hit one of the advert links by mistake and lost all. However, this one was killing me. I just couldn't see the way. Doubt that I would have finished it on paper; well, perhaps a day later. Wish I could have seen the picture!

Weird puzzle, a bit of a weird picture...
I think the church coming to you fufills your Sunday requirements, good works/deeds/thoughts come from the heart and not a building, although churches do have this incredible hushed and peaceful feeling when you walk in.

1. UP to 28;
2. bh1=35 excludes 35 in the rest of R1. UP to 32; 3. a89=1==a3=1--a3=8==a9=8--a9=2==b9=2 excludes b9=1; UP to 34;
4.h79=1 excludes g8=1;
5.i456=3 excludes g45=3;
6.b1=5==h1=5--h7=5==c7=5 excludes c23=5;
7. (g8=35)(h17=5)(b1a3=5)(agi4=5)(fi4=3) excludes f8=3; UP to More...

1) Start 23, UP to 28.
2) Naked pair 35 at bh1 forbids a1=5, g1=35, i1=35. UP 32.
3) Locked 1s at ab3 forbid g1=1.
4) b9=2 == b6=2 -- a56=2 == a9=2 -- a9=8 == a3=8 -- a3=1 == b3=1 forbids b9=1. UP 34.
5) Locked 1s at h79 forbid g8=1.
6) b1=5 == h1=5 -- h7=5 == c7=5 forbids More...

andrei could you explain step 2

Whoa- 2 min. I used no techniques, simple eliminations.

Andrei,

I know I've seen the matrix before but I don't remember the details. I can see how your last step works but it would be a pain to write as a chain. To write it as a chain, I would first have to show that if g8=5 then i4=5, and then I could write the forbidding chain g8=3 == i4=5 -- i4=3 == f4=3, and it would be nearly impossible to make sense of.

1) Start at 23 filled - the given puzzle. Unique Possibilities to 28. (UP 28)
2) pair 35 at b1h1 forbids gi1=3, agi1=5. UP 32.
3) b3=1 == a3=1 -- a3=8 == a9=8 -- a9=2 == b9=2 forbids b9=1 UP 34.
4) b1=5 == h1=5 -- h7=5 == c7=5 forbids c23=5.
5) a9=8 == a3=8 -- a3=5 == b1=5 -- h1=5 More...

Hi Andrei and Clark!
Good to have lots of proofs today!

It seems that we all have forbidden the 1 at b9. From there we part ways.

Andrei's matrix as a forbidding chain:
{g8=3 == g8=5 -- h7=5 == h1=5 -- b1=5 == a3=5 -- a4=5 == g4=5-- g8=5 == g8=3} == {g8=3 == g8=5 -- h7=5 == h1=5 -- b1=5 == a3=5 -- a4=5 == i4=5 -- i4=3 == f4=3} conclude at depth 5:
g8=3 == {g3=3,f4=3} forbids f8=3.

Also: g8=3 == g8=5 -- {{g4=5,h7=5} == h1=5 -- b1=5 == a3=5 -- ag4=5} == i4=5 -- i4=3 == f4=3
forbids f8=3

I prefer the shorter, latter presentation. Matrices I really do prefer, but... they do not write well at this venue.

Mark - Andrei's step 2 and my step 3 are basically the same, except we look at different one's at the beginning of the step.
Andrei's: If a89 contains 1 then b9<>1.
If a89 contains no 1, then a3=1.
Mine: If b3=1 then b9<>1, if b3<>1 then a3=1.
From here we follow the More...

Today's puzzle seems to have lots of depth 4 and depth 5 solutions/proofs available... I wrote the shortest depth 4 solution that I could find. Andrei's depth 5 solution is shorter then the depth 5 solutions that I found. In many ways, I prefer his as it has less steps, I think.
Would love to More...

Clark, I used the Triangular Matrix Pattern: this is a square matrix with each entry some set of possibilities (possibly empty) such that:
1. In each row at least one possibility must be true.
2. In each column j > 1, the top non-empty entry is in row (j-1), and every possibility in this More...

A choice between two alternatives was proven right up to the evd!

18:02 after setup. Guess 'WA' means different things to different people. Googled Beagle Bay to see where in Washington it was and discovered it was in Western Australia!

Andrei,
I get the following matrix for your step 7:

g8=3 g8=5
h7=5 h1=5
b1=5 a3=5
g4=5 a4=5 i4=5
f4=3 i4=3

Is this correct?

I see the problem with trying to write them. The spacing didn't stay in. Let's try this again with commas:

g8=3,g8=5
,h7=5,h1=5
,,b1=5 ,a3=5
,g4=5,,a4=5,i4=5
f4=3,,,,i4=3


Is this correct?

Jan-You make me laugh.

Oh wow, I look up to all of you in awe--
If given the problem (x-a)(x-b)(x-c) and so on until (x-z), what would the final result look like?

7:14

Harder tough than usual -- for me, anyway! Got to 32 filled, then had to make several guesses to finish.

Pretty little church.

I am not too sure about this matrix representation, but I think it is ok.

g8=3...g8=5
.......h7=5...h1=5
..............b1=5...a3=5
.......g4=5.. ........a4=5...i4=5
f4=3............... .........i4=3
Conclude f4=3 == g8=3 forbids f8=3

darn - seems that....'s don't work either:
g8=3___g8=5
_______h7=5___h1=5
______________b1=5___a3=5
_______g4=5 __________a4=5____i4=5
f4=3____________ _____________i4=3
Conclude f4=3 == g8=3 forbids f8=3

wish i could do the tough ones without guessing!

Clark and Steve, you got it!

ook - zero, as at one point you will have x-x = 0 and anything x 0 = 0

14:57
wet day on washing day!

Clark, Andrei, Steve and others; Where do I go to learn the particular notation and logic techniques you are using? TIA.

A bit over cast and a light mist of wet stuff some times. Loved the mother of pearl inlay I have been to baegle bay and the pic does not do justice to the real thing

15:16

10:12

7.11 - Not too difficult today, still raining here in Sydney town, Jennifer Aniston has just proved she certainly doesn't understand the Aussie sense of humour, reporter had her completely bamboozled!
Ah well, can't look like that and be smart as well.