reserve a,b,c,h for Integer;
reserve k,m,n for Nat;
reserve i,j,z for Integer;
reserve p for Prime;

theorem
  for m being Nat st m <> 3 holds
  not ex x,y,z being non zero Integer st
  x/y + y/z + z/x = m & x,y,z are_mutually_coprime
  proof
    let m be Nat such that
A1: m <> 3;
    given x,y,z being non zero Integer such that
A2: x/y + y/z + z/x = m and
A3: x,y,z are_mutually_coprime;
    (x = 1 or x = -1) & (y = 1 or y = -1) & (z = 1 or z = -1)
    by A2,A3,Th108;
    hence thesis by A1,A2;
  end;
