>881
　(1/k) = ∫[0,1] x^(k-1) dx.
∴ 納k=1,n] (1/k)*Ｃ(n,k)*(-1)^(k+1)
　= 納k=1,n] Ｃ(n,k)∫(-x)^(k-1) dx
　= ∫[0,1] {1-(1-x)^n}/x dx =
　= ∫[0,1] (1-y^n)/(1-y) dy
　= ∫[0,1] {1+y+(y^2)+･･･+y^(n-1)}dy
　= 納k=1,n] 1/k　〜　log(n).