(2+1)(2的二次方+2)(2的三次方+2)……(2的64次方)+1

问题描述:

(2+1)(2的二次方+2)(2的三次方+2)……(2的64次方)+1

1/(2+1)*(1/(2^2+1)*...*(1/(2^64)+1)
= 1/(2-1) * 1/(2+1)*(1/(2^2+1)*...*(1/(2^64)+1)
= 1/(2^2-1) * (1/(2^2+1)*...*(1/(2^64)+1)
= 1/(2^128-1)