... operation and that is associative and that includes an identity element and an inverse element. 4.2 A ring is a set of elements that is closed under two binary operations, addition and subtraction, ... 4.18 a. If An and Bn are both even, then 2 gcd(An+1, Bn+1) = gcd(An, Bn). But Cn+1 = 2Cn, and therefore the relationship holds. If one of An and Bn is even and one is odd, ... (32 bits) Thus, the bits no. 1 and 16 of the output are equal to ‗1‘. RD1 = LD0 F(RD0, K16) We are looking for bits no. 1 and 16 of RD1 (33 and 48 of the entire output). ...