5 Service functions of the Congruence package
  
  
  5.1 Additional information displayed by Congruence algorithms
  
  5.1-1 InfoCongruence
  
  InfoCongruence info class
  
  InfoCongruence  is  a special Info class for Congruence algorithms. It has 3
  levels: 0, 1 (default) and 2. To change the info level to k, use the command
  SetInfoLevel(InfoCongruence, k).
  
  In  the  example  below we use this mechanism to see more details during the
  Farey symbol construction for a congruence subgroup.