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      1 # Well Ordered
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      3 Abstract Math Chapter 10
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      5 **Definition:** A well order set has a definite smallest element. 
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      7 This is important because it is the basis for [Induction](Induction.md) as without it, there would be no way to prove that $S_n\implies S_{n+1}$ means that for something is true for all values in the set. 
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      9 A few examples of well ordered sets are $\N$, any known subset or provable subset of $\N$, the set {0,2,4,5646}, and infinitely many others. 
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     11 Some examples of non-well ordered sets include $\R$, $\Z$, and $\mathbb{Q}$