reserve i, n for Nat,
  x, y, a for Real,
  v for Element of n-tuples_on REAL,
  p, p1, p2, p3, q, q1, q2 for Point of TOP-REAL n;

theorem Th30:
  |(p, 0.TOP-REAL n)| = 0
proof
  reconsider f1=p as FinSequence of REAL by EUCLID:24;
  len f1=n by CARD_1:def 7;
  then 0*(len f1) = 0.TOP-REAL n by EUCLID:70;
  hence thesis by Th8;
end;
