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<math>\langle A, R \rangle</math> is an totally ordered class iff
 
<math>\langle A, R \rangle</math> is an totally ordered class iff
 
<ol>
 
<ol>
<li><math>R\subseteq A\times A</math></li>
+
<li>(R is a relation on A) <math>R\subseteq A\times A</math></li>
<li>(irreflexivity) <math>\forall x \in A \langle x,x \rangle \notin R</math></li>
+
<li>(irreflexivity) <math>\forall x \in A\, \langle x,x \rangle \notin R</math></li>
<li>(transitivity) <math>\forall x,y,z \in A \langle x,y \rangle \in R \wedge \langle y,z \rangle \in R \rightarrow \langle x,z \rangle \in R</math></li>
+
<li>(transitivity) <math>\forall x,y,z \in A\, \langle x,y \rangle \in R \wedge \langle y,z \rangle \in R \rightarrow \langle x,z \rangle \in R</math></li>
<li>(trichotomy) <math>\forall x,y \in A \langle x,y \rangle \in R \vee \langle y,x \rangle \in R \vee x=y</math></li>
+
<li>(trichotomy) <math>\forall x,y \in A\, \langle x,y \rangle \in R \vee \langle y,x \rangle \in R \vee x=y</math></li>
 
</ol>
 
</ol>
 
</p>
 
</p>

Latest revision as of 08:59, 1 June 2013

Equivalences of Well-ordered Relation

Definitions

$ \langle A, R \rangle $ is an totally ordered class iff

  1. (R is a relation on A) $ R\subseteq A\times A $
  2. (irreflexivity) $ \forall x \in A\, \langle x,x \rangle \notin R $
  3. (transitivity) $ \forall x,y,z \in A\, \langle x,y \rangle \in R \wedge \langle y,z \rangle \in R \rightarrow \langle x,z \rangle \in R $
  4. (trichotomy) $ \forall x,y \in A\, \langle x,y \rangle \in R \vee \langle y,x \rangle \in R \vee x=y $

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