 reserve G, A for Group;
 reserve phi for Homomorphism of A,AutGroup(G);
 reserve G, A for Group;
 reserve phi for Homomorphism of A,AutGroup(G);
reserve G1,G2 for Group;

theorem ThTrivialCyclicGroupCriterion: :: TH81
  for n being non zero Nat
  holds INT.Group n is non trivial iff n > 1
  by NAT_1:53,ThTrivialCyclicGroupCriterion1;
