1+1/2^2+1/3^2+1/4^2+…+1/100^2＜1+1/2^2+1/3^2+1/3*4+1/4*5...+1/99*100=1+1/4+1/9+（1/3-1/4）+(1/4-1/5)...+（1/99-1/100）=1+1/4+1/9+1/3-1/100=61/36-1/100＜61/36