November 20 - Relationships Work Like This

This is how relationships work:
1 Element, No Relationships: A
2 Elements, One Relationship: AB
3 Elements, Three Relationships: AB BC AC
4 Elements, Six Relationships: AB BC CD AC AD BD
5 Elements, Ten Relationships: AB BC CD DE AC AD AE BD BE CE
6 Elements, Fifteen Relationships: AB BC CD DE EF AC AD AE AF BD BE BF CE CF DF
7 Elements, Twenty-One Relationships: AB BC CD DE EF FG AC AD AE AF AG BD BE BF BG CE CF CG DF DG EG