In this task, you are given two lists A,B. Find the longest common subsequence in the lists A and B.

[3311, 7769, 9805, 5403, 9805, 'X', 'k', 9647, 'l', '3521', '2401', '2289', '4715', '7345', 'H', '2633', 'R', '5573', 'R', 2969, 'Q', 'h', 5097], [6611, 499, 5409, 's', 9485, 9981, 'x', 8121, 'l', '3521', '2401', '2289', '4715', '7345', 'H', '2633', 'R', '5573', 'J', 'I', 9867]
l, 3521, 2401, 2289, 4715, 7345, H, 2633, R, 5573