Question

1/1,1/2,2/2,1/3,2/3,3/3,1/4,2/4,3/4,4/4,...99/100,100/100,求这

Answer 1

由于1+2+3+...+n=n(n+1)/2,所以1/n+2/n+...+n/n=(n+1)/2.所以原数列和等于(1+1)/2 + (2+1)/2 + ...(100+1)/2 = 5150/2=2575.