Friday Puzzles #211

It's just as well I forgot to post this on Friday, as it turned out to be something of a disaster.  The idea here is that adjacent cells do not contain numbers whose sum is 5 or whose difference is 5.  Combinatorially speaking, this is equivalent to an XV Sudoku without any clues.  This probably explains why there were a few problems, and my thanks go out to Karel Tesař (of sudokucup.com fame) for helping to fix this puzzle.  This is really his puzzle! 

Anyhow, better late than never.  I've already got this week's puzzle ready so no worries there.  Enjoy!

    #248 Number 5 is not Alive Sudoku – rated medium

All puzzles © Tom Collyer 2009-13.