In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['t', 4949, 2605, 'y', '1073', '1027', 'J', '5087', '1741', 'W', 'i', 6835, 1859, 'W', 'h', 'R'], ['b', 5137, '1073', '1027', 'J', '5087', '1741', 'W', 'o', 'x', 'm']