It seems like it would be at least mildly complicated to reformulate, and a reformulation would be pretty fundamentally hetero-something. For example: There a

It seems like it would be at least mildly complicated to reformulate, and a reformulation would be pretty fundamentally hetero-something. For example: There are n pairs of people. Each pair has a type A person and a type B person. How many ways can they be arranged at a table such that the seats’ occupants alternate A,B,A,B etc and no one sits next to the person with whom they are paired. If you are paired with someone of the same type, you don’t fit into the problem statement :). If everyone is the same type as everyone else, and everyone is allowed to sit next to anyone else except their partner, then the answer will be different.