In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
['P', 3685, 'O', 419, '1513', 'b', 'R', 's', 'I', 'X', 'R'], [2375, 1747, 2621, '1513', 'b', 'R', 's', 'I', 'S', 'f', 'w', 'H']