The New Sudoku Players' Forum

[su_question]

Are there puzzles that exist that have only 1 unique solution but absolutely need trial and error at some point in order to solve them.

It's important to me that there is only 1 solution at the end of the game.

If so where can I find some puzzles with this unique property.

Also is there a special name given to these puzzles?

[Ruud]

You could take a look at the list of Hardest Sudokus.

However, for many of these puzzles, a solution has been presented using very advanced techniques. The definition of T&E seems to differ from player to player. One player could use a very complex move, which others would consider T&E. Also, new solving techniques are still being developed. A puzzle which requires T&E today may be solved with a new technique tomorrow.