CBSPALASS - 2306 - 4580 - BODE - FD23 BLASE 750 * inal - 81720 # 43 5 OF & Your friend Zack is counting ducks , there are two types ducks; the left-duck and the right- duck ; Notice that a left-duck can be dissected into four smaller ducks : three right- ducks ( once rotated ) and one left- duck . A second dissection results in each of these new ducks becoming four smaller ducks in a similar way . Let In denote the number of left- ducks after ~ such dissections into smaller ducks . That is , 10 = 1, 41 = 1, 12 = 10 ... Find a recurrence relation for In and find 15 . 15 = is the rx