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 a being logbase Real, f being Real_Sequence st a > 1 & f.0 = 0 & (
  for n st n > 0 holds f.n = log(a,n)) holds f is eventually-positive by Lm2;
