View source for Dynkin system/Definition 1

<noinclude>{{Extra Maths}}</noinclude>Given a set {{M|X}} and a family of subsets of {{M|X}}, which we shall denote {{M|\mathcal{D}\subseteq\mathcal{P}(X)}} is a ''Dynkin system''{{rMIAMRLS}} if:
* {{M|X\in\mathcal{D} }}
* For any {{M|D\in\mathcal{D} }} we have {{M|D^c\in\mathcal{D} }}
* For any {{M|1=(D_n)_{n=1}^\infty\subseteq\mathcal{D} }} is a [[Sequence|sequence]] of [[Pairwise disjoint|pairwise disjoint sets]] we have {{M|1=\udot_{n=1}^\infty D_n\in\mathcal{D} }}<noinclude>
==References==
<references/>
{{Definition|Measure Theory}}
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