I became interested in sudoku a few years back when they first started appearing in daily newspapers [strange to think in Japan the puzzle has been popular since 1986 but in the West only really since 2005], but now that I generally run rather than commute, I have little time for this thrilling hobby. An announcement I missed last summer concerning the hardest puzzle yet devised.
The new area of mathematical research into sudoku puzzles is fascinating. Apparently the smallest number of ‘givens’ [pre-filled in numbers] is 17 and the number of possible solutions for the ‘standard’ 9×9 puzzle is truly astronomical! 6,670,903,752,021,072,936,960.
Personally I prefer the puzzles were [no matter how hard] the solutions can be found from what is given; unlike many puzzles were you have to make choices between unknowns and start making multiple choices on top of choices. Somehow those puzzles, that can be solved without trial and error [known as a satisfactory puzzle in sudoku terminology] feel more … satisfying.
I have always been interested in Latin and Magic squares but what I am most interesting in with sudoku is how the maths of setting the puzzles works?