Problem
Let t_n be to of ways to tile an 2 times n array with 1 times 2 tiles and 2 times 2 tiles the number The 1 times 2 tiles may be placed horizontally or vertically. (a) Give t_1, t_2, t_3. (a) Derive a recurrence for t_n. Show your work! (b) Derive a generating function for the sequence.