In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[9605, 301, 3815, '3555', '8399', '2421', '6579', 'I', 'g', 's', 'a', 'T', 'w', 7419, 1721, 3853, 5703], ['J', 1425, 3627, 3619, '3555', '8399', '2421', '6579', 'I', 'g', 's', 'Y', 'R', 4039, 'y']