In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.
[3837, 4119, 'J', 'i', 'o', 'U', 'f', 'd', 'U', 9271, 9833, 'p', 1633, 'i', 'R', '23', 'J', '9299', 'u', 'l', '761', '7315', 'Y', '7993', '4747', 'a', 'x', '257', 'k', 'G', '2571', '6909', '4581', 'd', 'c', 'a', 'Q'], [299, 7921, 'b', 9191, 4437, 6045, 2423, 'c', 5503, 'B', 809, 6679, 'P', 473, 7911, 'F', 'R', '23', 'J', '9299', 'u', 'l', '761', '7315', 'Y', '7993', '4747', 'a', 'x', '257', 'k', 'G', '2571', '6909', '4581', 'o', 'M', 'u', 1533, 421, 8213, 331, 'l', 'F', 3749, 1799, 'N', 3561, 8367, 4789, 4257, 'j']