I have a similar problem. It's tennis rotations for doubles tennis.

4,5, and 6 courts, 4 people per court. 3 rotations. No one plays on the
same court with another person twice.

There are multiple solutions. So we added... what is the solution(?) so
that there is the least movement. Meaning, each player moves after each
round. You want to minimize the distance moved by all people during all
three rounds.

Turned out there are multiple solutions to that too so we added: Make
everyone's movement as equal as possible. Meaning... one person doesn't
stay on the same court 3 times while another moves 4 courts both times.

I wrote a program in Power Basic about 10 years ago that solved it
through trial and error. It essentially just randomly makes movements,
measures the things looked for and saves the best ones. I can't port it
into vb because too many functions are unavailable in vb, especially the
swap function for arrays.

John




Dana DeLouis wrote:
In combination study, it also sometimes goes by the name of "Social
Golfer."
The best you can do is 5 seatings before duplicates...
Here's a link that is pretty good...

The Social Golfer Problem
http://www.cs.brown.edu/~sello/golf.html

These are one of the hardest Combo problems to solve.