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<mathematics> A set with a total ordering and no infinite descending chains. A total ordering "<=" satisfies
x <= x x <= y <= z => x <= z x <= y <= x => x = y for all x, y: x <= y or y <= xIn addition, if a set W is well-ordered then all non-empty subsets A of W have a least element, i.e. there exists x in A such that for all y in A, x <= y.
Ordinals are isomorphism classes of well-ordered sets, just as integers are isomorphism classes of finite sets.
(1995-04-19)
Nearby terms: well-behaved « well-connected « well-known port « well-ordered set » WEP » Wesley Clark » Western Digital Corporation
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