Observam ca (2+2)x2 = 2^3, si mai departe ca ((2+2)x2 +2^3)x2=2^5...
mai departe prin acelasi principiu v a insemna si ca (((2+2)x2+2^3)x2+2^5)x2...+2^2001)x2=2^2003 => ca ((2+2)×2+2^3)×2+2^5).2+..+2^2001)×2+2^2003 = 2^2003+2^2003 =(2^2003)(1+1) = 2^2004
