My sister (a high school teacher) came and asked me the following question:
"Hi bro I'm having 28 new students in my class. They need to know each other. So I want everybody to work together in small groups. I'm thinking splitting them in groups of 4 and having 9 rounds. Then everyone meets 3 people in every round and after 9 rounds they have been in a group with everybody. Isn't that pretty. But I'm just missing an algorithm to set up the groups and you are a CS-master that must a be a job for you!"
I have been trying to figure it out, but the combinatoric search space is to big. Do you have a good suggestion for a way to create these groups.