Hello. I'm stuck on another proof. Can anyone help me with this problem?

Let S of N be the Nth partial sum of the harmonic series

a) Verify the following inequality for n=1,2,3. Then prove it for general n.

+ + + ... +

b) Prove that S diverges by showing that for N=

Hint:Break up Sn into n+1 sums of length 1,2,4,8..., as in the following:

S of = 1 + (1/2) + (1/3 + 1/4) + (1/5 + 1/6 + 1/7 + 1/8)

Thank you!