出典:Wikipedia
出典:『Wikipedia』 (2011/01/30 02:20 UTC 版)
In the mathematical field of order theory, a containment order is the partial order that arises as the subset-containment relation on some collection of objects. In a simple way, every poset P = (≤, X) is (isomorphic to) a containment order. To see this, associate to each element x of X the set