reserve a,b,p,k,l,m,n,s,h,i,j,t,i1,i2 for natural Number;

theorem
  i gcd i = i
proof
A0: i is Nat by TARSKI:1;
  for m being Nat st m divides i & m divides i holds m divides i;
  hence thesis by A0,Def5;
end;
