reserve c for Complex;
reserve r for Real;
reserve m,n for Nat;
reserve f for complex-valued Function;
reserve f,g for differentiable Function of REAL,REAL;
reserve L for non empty ZeroStr;
reserve x for Element of L;

theorem Th24:
  seq(n,x).n = x
  proof
    dom(0_.L) = NAT;
    hence thesis by ORDINAL1:def 12,FUNCT_7:31;
  end;
