optimal [(0, 1, 2, 3), (0, 1, 4, 5), (0, 2, 4, 6), (0, 3, 5, 6), (1, 2, 5, 6), (3, 4)] (if conjecture about Ferrers Diagram Rank-Metric Codes is true: 16781960 with optimal [(0, 1, 2, 3), (0, 1, 4, 5), (0, 2, 4, 6), (0, 3, 5, 6), (1, 2, 5, 6), (3, 4)])
) : 16781960