(3+1)(3^2+1)(3^4+1)(3^8+1)(3^16+1)=(3-1)(3+1)(3^2+1)(3^4+1)(3^8+1)(3^16+1)/2=(3^2-1)(3^2+1)(3^4+1)(3^8+1)(3^16+1)/2=(3^4-1)(3^4+1)(3^8+1)(3^16+1) /2=(3^8-1)(3^8+1)(3^16+1)/2=(3^16-1)(3^16+1)/2=(3^32-1)/2
