Sudoko

Sudoku puzzles have become a popular pastime of late and here in the Department of Mathematical Sciences Prof. Peter Higgins has developed a new variant of them which we call circular, or target, sudoku. Prof. Higgins' puzzles began appearing in the Sunday Telegraph in June 2005, but just in case you have missed them we have one here for you to have a go at. The instructions are given with the puzzle.

• Circular Sudoku Puzzle

If you would like to see the solution to the puzzle then send an e-mail to Professor Higgins.

For a further collection of puzzles there is a book of Circular Sudoku puzzles now available, you can download CircularSudoku.ps for a further taster (please note you need a postscript viewer such as GhostView to open it) or you can now buy a Circular Sudoku electronic game.