6 * (7+1) * (7^2 + 1) * (7^4 + 1) * (7^8 + 1) + 1=(7-1)*(7+1)*(7^2+1)*(7^4+1)*(7^8+1)+1=(7^2-1)*(7^2+1)*(7^4+1)*(7^8+1)+1=(7^4-1)*(7^4+1)*(7^8+1)+1=(7^8-1)(7^8+1)+1=(7^16-1)+1=7^16
