Set (card game) 9th in the 1995 "Deutscher Spiele Preis". Several games can be played with these cards, all involving the concept of a "set". A set consists of three cards satisfying "all" of these conditions: The rules of "Set" are summarized by: If you can sort a group of three cards into "two of ____ and one of ____", then it is not a set. For example, these three cards form a set: Given any two cards from the deck, there is one and only one other card that forms a set with them. In the standard Set game, the dealer lays
Partition of a set into the connected components of the subgraph formed by the given set of edges. In this way, the lattice of partitions corresponds to the lattice of flats of the graphic matroid of the complete graph. Another example illustrates the refining of partitions from the perspective of equivalence relations. If "D" is the set of cards in a standard 52-card deck, the "same-color-as" relation on "D" – which can be denoted ~ – has two equivalence classes: the sets {red cards} and {black cards}. The 2-part partition corresponding to ~ has a refinement that yields the "same-suit-as" relation ~, which has