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<b>let </b><font color="Maroon">c<sub>1</sub></font>, <font color="Maroon">c<sub>2</sub></font> be    <a href="hidden.html#M1">set</a> ;<br/>



<b>assume </b><a NAME="E1:6"/>
<font color="Maroon">c<sub>1</sub></font> <a href="xboole_0.html#R1">misses</a> <font color="Maroon">c<sub>2</sub></font>
 ;<br/>

<a NAME="E2:6"/><b>then </b>
 <a href="ff_siec.html#K2" target="_self">PTempty_f_net</a> <font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font> <a href="hidden.html#R1">=</a>  <a href="net_1.html#G1">Net</a>(# <font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font>,<a href="xboole_0.html#K1">{}</a>  #)
 
<b>by </b><i><a class="ref" href="ff_siec.html#D4" target="_self">Def4</a></i>;<br/>
<b>hence </b><a NAME="E3:6"/>
( the <a href="net_1.html#U1">Places</a> of <span class="p1">(<span class="default"><a href="ff_siec.html#K2" target="_self">PTempty_f_net</a> <font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>1</sub></font> &amp; the <a href="net_1.html#U2">Transitions</a> of <span class="p1">(<span class="default"><a href="ff_siec.html#K2" target="_self">PTempty_f_net</a> <font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font></span>)</span> <a href="hidden.html#R1">=</a> <font color="Maroon">c<sub>2</sub></font> &amp; the <a href="net_1.html#U3">Flow</a> of <span class="p1">(<span class="default"><a href="ff_siec.html#K2" target="_self">PTempty_f_net</a> <font color="Maroon">c<sub>1</sub></font>,<font color="Maroon">c<sub>2</sub></font></span>)</span> <a href="hidden.html#R1">=</a>  <a href="xboole_0.html#K1">{}</a>  )
 ;<br/>


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