(2-1)(2+1)(2^2+1)(2^4+1)…(2^32+1)
=(2^2-1)(2^2+1)(2^4+1)…(2^32+1)
=(2^4-1)(2^4+1)…(2^32+1)
=……(连续运用平方差公式)
=2^64-1