Re: The road to Artificial Intelligence

Is 3 seconds even enough to generate
unique Sudokus? How many trials would be
needed? The uniqueness problem
seems to have no useful reduction,
already the question whether a partial
latin square has a unique solution
is NP complete?
Finding Another Solution
T. Yato & T. Seta - 2002
https://academic.timwylie.com/17CSCI4341/sudoku.pdf
Mild Shock schrieb:

Now I have the feeling there are no difficult 9x9
Sudokus for the computer. At least not for computers
running SWI-Prolog and using CLP(FD) with the global
constraint all_distinct/1.
 I was fishing among the 17-clue Sudokus, and the
hardest I could find so far was this one:
 /* Gordon Royle #3668 */
problem(11,[[_,_,_,_,_,_,_,_,_],
             [_,_,_,_,_,_,_,1,2],
             [_,_,3,_,_,4,_,_,_],
             [_,_,_,_,_,_,_,_,3],
             [_,1,_,2,5,_,_,_,_],
             [6,_,_,_,_,_,7,_,_],
             [_,_,_,_,2,_,_,_,_],
             [_,_,7,_,_,_,4,_,_],
             [5,_,_,1,6,_,_,8,_]]).
 But SWI-Prolog still does it in around 3 seconds.
SWI-Prolog does other 17-clue Sudokus in less than 100ms.
 Are there any 17-clue Sudokus that take more time?