2. In Example 3 with m = 209, Bob receives from Alice the pair ((1,1,0,1,0), 104). What letter did Alice send Bob? [You may want to utilize an online modular power calculator or MAPLE in this problem]

Example 3. Alice wants to send Bob a letter. Bob chooses m 209 which he knows factors as 11 . 19. He sends Alice the number 209 but not the prime factorization The letter Alice wants to send Bob is "r", or 18, or w = (10010) (base 2). She picks a random starting value xo- 13 and computes a BBS sequence starting from To - 13 by successively squaring modulo m = 209: (x1, 22, 23, 34, r5, ^6) (169,137,168,9,81,82) 82, the key, and reduces the other numbers mod 2 She saves 6K to get She finds kb