reserve c, c1, c2, d, d1, d2, e, y for Real,
  k, n, m, N, n1, N0, N1, N2, N3, M for Element of NAT,
  x for set;

theorem
  for n st n >= 9 holds (n+1) to_power 6 < 2*(n to_power 6) by Lm29;
