I have invented it, long ago. It's a test how clever a class or a community is.
Say, you have all white chess pieces on a chessboard. How many connections can they have at the most. A connection is when a piece is "attacking" or "covering" another piece. If this piece is "shooting" back, it's already two connections there between the two.
In the initial position there are 20 connections. 4 by the rooks, 4 by the bishops, 2 by the knights, 5 by the queen, 5 by the king.
Just give me the maximal number.