reserve i,j,k,n,m,l,s,t for Nat;
reserve a,b for Real;
reserve F for real-valued FinSequence;
reserve z for Complex;
reserve x,y for Complex;
reserve r,s,t for natural Number;

theorem
  m gcd 0 = m
proof
  set M = m gcd 0;
  m divides 0 by NAT_D:6;
  then
A1: m divides M by NAT_D:def 5;
  M divides m by NAT_D:def 5;
  hence thesis by A1,NAT_D:5;
end;
