When I pasted the string into SudoCue I got the following message:
I looked at at the options, all solving techniques were enabled. So I started to step through the puzzle. But somewhere along the road I got an invalid arrangement (3 numbers for 4 cells on D\), so I started over and stepped through it, only using SudoCue. What a surprise: I ran in the same problem again!?!Too difficult sudoku
This is a valid puzzle 24, but it cannot be solved with your current solver settings. The solver can only solve 53 of 81 cells. Either the solver settings are incorrect or or this sudoku is too difficult.
Also, if I tell SudoCue to solve it it tells me "The puzzlr has no solution".
So, Ruud, did you want to test us? See who even tries to solve these things? Or are there some mean not-yet-invented techniques you have to use? Or did I miss something fundamental?
Peter