From: mightydreams@gmail.com   
      
   If I am given a string   
   a^nb^na^n   
      
   where a^n is a to the power n is this language an example of   
   a) context free,   
   b)non context free,   
   c) not context free but whose complement is CF,   
   d) context free but whose complement is not context free.   
      
   The answer in book is given to be b and c and I am not able to   
   understand what is complement of CF language.   
   Any help would be appreciated.   
   Thanks.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)