Just found it again!  Here’s one of the grids I generated:

     0 1 2    3 4 5    6 7 8
   ----------------------------
0  | . . 9  | . 6 5  | 8 3 .  |
1  | . . 6  | 4 . .  | . . .  |
2  | . 4 .  | 7 . 9  | 6 . .  |
   ----------------------------
3  | . 3 2  | . . .  | . . .  |
4  | . . .  | 3 7 2  | . . .  |
5  | . . .  | . . .  | 9 2 .  |
   ----------------------------
6  | . . 5  | 1 . 7  | . 8 .  |
7  | . . .  | . . 6  | 4 . .  |
8  | . 7 4  | 5 8 .  | 1 . .  |
   ----------------------------

Enjoy!