Sudoku Puzzles

The very tough puzzle of February 20, 2007 is the subject of a blog magazine. The first page of my analysis of that diabolicaly tough puzzle is currently available. The balance of the pages will become available as they are finished. The proof that will be presented is a notch beyond trivial.
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Is this the outside of last night's photo? Very impressive.

me first

Good morning to all! A picture from Wagdy Kamel perhaps?

10:33...One mistake that gave me information.

Good Morning All - Maybe some sun today!!! I hope

Took me over an hour to solve.

Hi Everyone .
My another photo of 'Cairo/Egypt',and for the good luck it is the outside view of yesterday photo of 'Mohamed Ali Mosque' on top of the 'Cairo Citadel'.

Emelia :Now you can see the view as you requisted yesterday.

Nice mAen to all.

ouch...this puzzle hurt LOL forgot the timer, but it was long

just over 22 mins with a few mistakes. using the physical possibilities screws me up. using mental possibilities makes the puzzle solvable!

wagdy kamel,

thanks for yesterdays info. i enjoy learning something new everyday

Impressive from the exterior as well. Thanks, Wagdy.

Good pic Wagdy Kamel, and two days in a row! Very impressive!!

I needed to use the possibilities to finish this one.

timer stuck at 1:45; took me a while. Thanks for the pic Wagdy, the mosque is very beautiful.

Beautiful Photo Wagdy and yes it is very impressive, love the domes and spires, thank you.

One of those challenging puzzles that i have tried. Impressive mosque.

Enjoying seeing photos from Egypt, Thanks Wagdy

Hi Wagdy Great photo, brought back memories of my visit to Egypt two years ago. In fact the mosque was a part of our tour. Thanks

A proof for tough sudoku of 03 05 2007:

1) Start at 22 filled - the given puzzle. Unique Possibilities to 22 filled. (UP 22).
2a) Locked 7's at a23 forbids a46=7
2b) i1=6 == c1=6 -- c1=9 == c6=9 -- c6=7 == df6=7 -- f4=7 == f4=5 -- f2=5 == h2=5 forbids h2=6 UP 25
3a) f9=6 == f6=6 More...

SE=8.4

1.UP=22
2.(9=8)h4-h8=h7g9-(49')h7g9=(9)i79 => i4h7<>9 UP=23
3.kraken column(7)e258 => e5<>3 STE.
(7)e8-i8=(7-9)i7=d7-(9=3)e9
||
(7)e2-(17=5)af2-(567=3)d6f46
||
(7)e5