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 >= 1 holds
    ((n+1)/n) to_power n <= ((n+2)/(n+1)) to_power (n+1) by Lm42;
