In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['b', 551, 'F', 't', 'I', 'B', 'r', '6771', '9513', 't', 235, 'I', 9425], ['x', 'D', 'Y', 2485, 3247, 'I', 'B', 'r', '6771', '9513', 'f', 4619]