Soduku

[Mikael Olofsson]

Jonathan Gardner wrote:
> How do you have a 16x16 grid for soduku? Are you using 16 digits? 0-F?
> 
> The one I am using has 9 digits, 9 squares of 9 cells each, or 9x9
> cells.

What alphabet you use is irrelevant. Sudokus has really nothing to do 
with numbers. You can use numbers, as well as letters, fruits, or car 
models. Numbers just happen to be nice to use as alphabet for fairly 
small sudokus. The hobby electronics magazine elektor at

     http://www.elektor-electronics.co.uk/

uses 0-F for their 16x16 sudokus.

You can make sudokus of more or less any size. In the kids department at

     http://www.dailysudoku.co.uk

you can find 4x4 and 6x6 grids. Apart from those and the standard 9x9, I 
have also seen 12x12, 16x16 and 25x25. You could make them 8x8 or 99x99 
if you wish. Those numbers should be non-primes, though, since the 
pattern of sub-blocks breaks if the numbers are primes.

Perhaps I should mention the three-dimensional one (9x9x9) that someone 
showed me at work. That particular one was a bore, since it contained 
too much patterns. Or the two orthogonal ones, where you have two 9x9 
sudokus in one with interrelations...

Finally, dailysudoku also has what they call squiggly sudokus, e.g.

 
http://www.dailysudoku.co.uk/sudoku/squiggly/archive.shtml?year=2006&month=02&day=15

By the way, if I'm not completely mistaken, there are only two 
non-equivalent solutions to the 4x4 grid. The equivalence relations 
taken into account are then the following:

   Permutations of the alphabet.
   Interchanging interchangeable rows or columns.
   Transpose - as in matrix transpose - of the whole grid.

Enough off-topic for now
/MiO