To err is human... I think Roger's explanation is accurate, and the
puzzle you present has no solution. If the intent was to solve the
Sudoku from the link to USA Today, then I would expect that:
10#.3 3 3 3$ , u20130522_corrected
900 30 2
3 26 0
20 190 430
350 60 90
2 40 715
70 50 26
49 75 80
0 610 500
100 80 3
sudoku u20130522_corrected
9 8 7 5 3 4 1 6 2
4 1 3 7 2 6 9 5 8
5 2 6 1 9 8 4 3 7
3 5 1 2 6 7 8 9 4
6 9 2 8 4 3 7 1 5
8 7 4 9 5 1 3 2 6
2 4 9 3 7 5 6 8 1
7 3 8 6 1 2 5 4 9
1 6 5 4 8 9 2 7 3
would satisfy ... the difference is in atom 0 2 0 (i.e. was 20, not 2,
in the online puzzle)
On 2013/05/30 13:33 , Roger Hui wrote:
Depends on what you mean by a proof. If the sudoku verb in the J Wiki
essay fails to find a solution that means that there isn't one.
If you want a proof that is more convincing to a human then study the
phrases following "The following phrases show the intermediate steps
leading to a solution". The algorithm basically is to find all the forced
moves, resulting in F. Then pick a square of F with the fewest number of
possible moves, try each possible move, and if none of them lead to a
solution, then the initial grid does not have a solution.
On Thu, May 30, 2013 at 10:20 AM, Raul Miller <[email protected]> wrote:
http://www.jsoftware.com/jwiki/Essays/Sudoku
http://puzzles.usatoday.com/sudoku#/2013/05/22
(caution: that usatoday page often has a 30 second preroll ad,
hopefully that will be toned down before too long.)
$u20130522
81
10#.3 3 3 3$u20130522
900 30 2
3 26 0
2 190 430
350 60 90
2 40 700
70 50 26
49 75 80
0 610 500
100 80 3
sudoku u20130522
|index error: free
Is this really a sudoku puzzle without a solution?
If so, what's a simple way of proving this?
Thanks,
--
Raul
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