你确定提没错?没错的话就用以下解法
原式=(2+1)(2^2+1)(2^4+1）……(2^(2n-1)+1)
=1x(2+1)(2^2+1)(2^4+1)……(2^(2n-1)+1)
=(2-1)(2+1)(2^2+1)(2^4+1)……(2^(2n-1)+1)
=(2^2-1)(2^2+1)(2^4+1)……(2^(2n-1) +1)
=……
=(2^2n-1 )(2^(2n-1)+1)
=2^4n-1-2^2n-1+2^2n-1

算式中有空的地方就是那单独的有指数的步骤