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Tough Sudoku for 8/November/2005


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

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Submitted by: sudoku lover

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It's my birthday and I solved it first!!!

Dolphins are humans too...
Happy Birthday. This one's tougher than yesterday.
didnt time but worked it out in approx 20 mins
8:41........A very Happy Birthday to you Omer, have a good one!
Happy b-day to you Omer !
Happy birthday Omer!
A challenge for every one : today's puzzle is equivalent to one and only one of these : 10-30, 10-31, 11-01, 11-02, 11-03, 11-04, 11-06. find which one. Winners win :
1) my highest consideration,
2) their names quoted in today's proof page.
Good luck !
Have a good one all
Let me remind that 2 puzzles are equivalent when one is obtained from the other simply by renaming numbers (e.g. exchanging 5s and 4s) and mixing some columns, rows, blocks(e.g. exchanging rows R1 and R3) so that any solution/proof of the first comes transformed in a solution/proof of the second (hence, if first has a single solution, so has the second).
Simple eliminations to 64 filled
Look at d5=6, f5=2. FC of 6 makes e3/g3=6 so d5=2 and f5=6 to solution
gb - what d'ya reckon?
Happy Birthday Omer :o)
20:04 Realized I made a mistake about 9 mins into the puzzle (forgot to put in a possibility which just ruined the chain!) Happy bday Omer! GB, j'espere tout aller bien chez vous, je m'inquete pour ma famille au banlieu de Paris
.....off to take up gb's challenge!
sweetie, I hope everything is allright with your relatives.
I live in the country, our village is 120 people, never lock house and cars' doors (even sometimes forget the key on the door...), seems there are two France...
you're right gb - there are definitely two 'France' - I feel as though all the trouble is happening a million miles away
Glad to hear all is well with both gb and Fiona! My family is not near the north suburbs, but I do have relatives near the south (vers Orly). And I heard on the news that there was some violence near the southern suburbs of Paris...
7:28, same as the medium!

Happy Birthday Omer! How old are you now?
18.39 and glad the French cousins are OK.Sounds scary.They should just stop.
likewise happy that our friends from France are OK. Hope the troubles end soon.

belongs to tough category allright as i had to use two nishio moves to solve it. we can say easy of the toughs. However no comparison to yesterday. That was much too easy John
Happy birthday Omer! And hear hear on good news all well with French friends - hope your family's okay too, sweetie. No time - no numbers!
Say, gb?
The one of 10-30 has a striking resemblance to this one...
Price money can be dropped on my regular bankaccount

Ciao & merci beaucoup
Hello Spucko,hows Enak Opsokcub?(gosh that's hard to type!)
I think he's okay, di! Haven't heard of him for a few days...I'll send him your best wishes, if that's what you want?
Last time I saw him, he was preparing for the hunt of a king, something with daggers and the like - about to go to Wales in order to meet some Brian(?) he said...I don't know the details...
gb - i'm going for 10-30 cos thats the only one that start with 20 filled - but its how I prove it I'm working on!
Too late, Deb!
Stop searching...I already won...
Typical..... see, I'm lost in my thousands of pieces of paper and miss the boat again!
So Buccky - how d'ya do it....
Just look at the two puzzles, Deb...
The one of 10-30 is the ONLY one, that comes close (even very close) to the layout of todays. So, if GB states, that there are two of them equivalent (and who would dare to doubt GB??!!), then it MUST be that one.
Satisfactory, Deb?

And sorry by the way...
Shouldn't there be an A in that nom de plume?Or am I too fussy,Bucksa?Do we get in trouble for chatting in 'tough'?Wales is chilly this time of year'I hope they're wearing more than thongs.Yes,please give him my regards.:}
I will, di!
And sorry for the mistakes in the mangaars...you have found out how hard they are to type, no?
Give or take a letter, who cares?
Bocks - yeah, well I can see its similar - but I wanna PROVE it!

...and so you should be sorry - talk about rain on my parade... or maybe I should just try refreshing the page B4 I type...
Yep.Off home now,as it's half past three in the morning.Doog thing,Ukboc.
Bucko has been first, but he used what we call a 'meta-proof' ! So If Deb finds the real 'dictionary' translating 10-30 in today's, no arguing, she will deserve the title of 'first regular here having understood the concept well enough to apply it concretely.'.
A tip, Deb : First exchange rows R123 and rows R789, then samely exchange columns Cabc and Cghi.
Done it - just dont know how to write it dictionary-wise!
I've done it on blocks - gb tell me what the proper way to write it is.

10-30 is equiv to 11-8 - blocks are,
Bb8 (11-8) =Bh2 (10-30)
Be8 = Be2
Bh8 = Bb2
Bb5 = Bh5
....I think....!
gb - hang on.... thats not right
Look, gb!

This is not funny...as far as I know, you did not require any proof whatsoever; you just stated:

' ..find which one '

which I did, didn't I? ;)
Ignore that last one - I need to go one further step to get 10-30 to 11-8 but I'll end up divorced if I dont get the dinner on the table!

I'll be back later to work out what I've done!

Spuks - I concede you are the greatest, the best and the first.....
No, no, no, NO!
Hats off for Deb!
You're the one, that's really trying to prove it; no doubt I could do that (some interchanging of rows and columns needed, maybe a rotation of 180 dg, then some interchanging of numbers here and there).
Just don't feel like it, but you do! Good for you!
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