[math-fun] a difficult sudoku

15 Feb 2010

      Hello,

  here is a sudoku for the amateurs,

+-------+-------+-------+
| 1 . . | . . 7 | . 9 . |
| . 3 . | . 2 . | . . 8 |
| . . 9 | 6 . . | 5 . . |
+-------+-------+-------+
| . . 5 | 3 . . | 9 . . |
| . 1 . | . 8 . | . . 2 |
| 6 . . | . . 4 | . . . |
+-------+-------+-------+
| 3 . . | . . . | . 1 . |
| . 4 1 | . . . | . . 7 |
| . . 7 | . . . | 3 . . |
+-------+-------+-------+

apparently the is one of the toughest there is.

- can anyone do this ?

Simon Plouffe