reserve x for set;
reserve a, b, c for Real;
reserve m, n, m1, m2 for Nat;
reserve k, l for Integer;
reserve p, q for Rational;
reserve s1, s2 for Real_Sequence;

theorem Th51:
  1 #Q p = 1
proof
  thus 1 #Q p = (denominator(p)) -Root 1 by Th37
    .= 1 by Th20,RAT_1:11;
end;
