(-2的2次幂分之1)*(1-3的2次幂分之1)*(1-4的2次幂分之1)*.*(1-99的2次幂分之1)*(1-100

（1-1/2^2)(1-1/3^2)..(1-1/100^2)
=(1+1/2)(1-1/2)(1+1/3)(1-1/3)(1+1/4)(1-1/4)...(1+1/100)(1-1/100)
=1/2*(3/2)(2/3)(4/3)(3/4)(5/4).(99/100)(101/100)
=1/2*101/100
=101/200