Simply Sudoku Blog

In the simplest sense, I would expect it to be strongly related to the number of clues, and that the clues given are random. However, this is apparently not true as my Droid gave 26 clues to an extreme puzzle, and 22 to a hard one. Just curious.

Thanks in advance.

The number of possible alternatives for each remaining square. If arranged correctly, a puzzle with 15 clues could be easy. It is all about the initial arrangement and the possible different #’s remaining for each open square.