f(3) = 1/3 + f(2)/3 = 1/3 + 1/6 = 1/2.

f(4) = 1/4 + 2/4 f(3) = 1/4 + 1/2 1/2 = 1/2.

f(5) = 1/5 + 3/5 1/2 = 1/2.

f(6) = 1/6 + 4/6 1/2 = 1/2.