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    Primary Decomposition 
 
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      Task:  | 
   Decompose the variety defined by
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    I=(y2z2-x2y3-xz3+x3yz
    , y2z-xz2)
     
   
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   into its irreducible components via primary decomposition.
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      LIB "primdec.lib";
       
      ring r=0,(x,y,z),dp;
       
      ideal i=y^2*z^2-x^2*y^3-x*z^3+x^3*y*z,y^2*z-x*z^2;
       
      primdecGTZ(i);
       
      
      
      
	
	  
	    
	      
		[1]:
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		[1]:
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		_[1]=-y2+xz
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		[2]:
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		_[1]=-y2+xz
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		[2]:
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	       | 
	      
		[1]:
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		_[1]=z2 
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		_[2]=y
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		[2]:
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		_[1]=z 
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	       | 
	      
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		_[2]=y
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		[3]:
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	       | 
	      
		[1]:
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		_[1]=z
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	       | 
	      
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		_[2]=x2
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		[2]:
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		_[1]=z 
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		_[2]=x
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     The result we got is a list of 3 tuples of ideals, where the
     first ideals are the primary and the second ideals are the
     corresponding prime ideals. Hence,
    
     
     
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