Mathematicians Solve Minimum Sudoku Problem

[n2doc]

Sudoku fanatics have long claimed that the smallest number of starting clues a puzzle can contain is 17. Now a year-long calculation proves there are no 16-clue puzzles
KFC 01/06/2012

Sudoku is a number puzzle consisting of a 9 x 9 grid in which some cells contain clues in the form of digits from 1 to 9. The solver's jobs is to fill in the remaining cells so that each row, column and 3×3 box in the grid contains all nine digits.

There's another unwritten rule: the puzzle must have only one solution. So grids cannot contain just a few starting clues.

It's easy to see why. A grid with 7 clues cannot have a unique answer because the two missing digits can always be interchanged in any solution. A similar argument explains why grids with fewer clues must also have multiple solutions.

But it's not so easy to see why a grid with 8 clues cannot have a unique solution, or indeed one with 9 or more clues.

more
http://www.technologyreview.com/blog/arxiv/27469/?p1=blogs

[caraher]

1. I though this was minimum Sudoku

[BadgerKid]

2. How about a 1x1 sudoku?

[Glassunion]

3. You asshole...

You had to put the puzzle up didn't you. Couldn't have just posted the text from the article could you.

Now I have to solve it... I thought I was over my addiction, but noooooo. Now I'm off the wagon doing this damn puzzle.

Damn it!!!

[Dead_Parrot]

4. You too, huh?

Sigh...