<?xml version="1.0"?>
<!DOCTYPE specification SYSTEM "seed.dtd">


<specification>

<start idref="Pres"/>

<fragment_sigma value="1"/>

<variables id="V">
  <symbol value="x"/> 
  <symbol value="y"/> 
  <symbol value="z"/> 
</variables >

<union id="Pres">
 <child idref="O"/>
 <child idref="N"/>
 <child idref="Atomic"/>
</union>


<union id="Terme">
 <child idref="V"/>
 <child idref="I"/>
 <child idref="Plus"/>
</union>

<binary_sym_neq id="Atomic">
  <symbol value="="/> 
 <child idref="Terme"/>
</binary_sym_neq>


<constants id="I">
  <symbol value="0"/> 
  <symbol value="1"/> 
</constants>


<union id="C">
 <child idref="V"/>
 <child idref="I"/>
</union>

<sequence id="Plus">
  <symbol value="+"/> 
  <child idref="C"/>
</sequence>


<sequence id="O">
  <symbol value="Or"/> 
  <child idref="nO"/>
</sequence>

<unary id="N">
  <symbol value="Not"/> 
  <child idref="nN"/>
</unary>

<union id="nO">
 <child idref="N"/>
 <child idref="Atomic"/>
</union>

<union id="nN">
 <child idref="N"/>
 <child idref="Atomic"/>
</union>



</specification>

