In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[3855, 7505, 'A', 'H', 'N', 'M', '9971', 'P', '7571', 'A', 'i', '3651', 'Y', 'D', 'N', 'A', 'N', 2373, 'd', 9087, 7117], ['R', 9511, 'N', 'M', '9971', 'P', '7571', 'A', 'i', '3651', 'Y', 'D', 'N', 'i', 9125, 'O', 355, 6831]