|Finnish mathematician has concocted what he claims to be the toughest ever Sudoku|
The Finnish mathematician Arto Inkala has come up with what he describes as the 'Everest' of numerical games in order to try and test the sharpest minds in the world and, presumably, leave the rest of us scratching our heads.
Generally, the brain teasers are scored on difficulty with a range from one to five, the former being the easiest and the latter the hardest. Mr Inkala feels that this particular test would come with an eleven rating.
The point that makes this particular teaser so tricky is the number of deductions needed to fill in a single number on the grid.
Read more... | Try the puzzle