  
  
  [1m[4m[31mReferences[0m
  
  [33m[W98]  [0m[1m[31mWirsching,  G.  J. [0m, [34mThe dynamical system generated by the $3n+1$
  function[0m,  Springer-Verlag,  Lecture  Notes in Mathematics, [34m1681[0m, Berlin
  (1998), viii+158
  
  
  
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