A139552 Least common multiple (or lcm) of {1, 2, ..., n/3}.

1, 1, 1, 1, 1, 1, 2, 2, 2, 6, 6, 6, 12, 12, 12, 60, 60, 60, 60, 60, 60, 420, 420, 420, 840, 840, 840, 2520, 2520, 2520, 2520, 2520, 2520, 27720, 27720, 27720, 27720, 27720, 27720, 360360, 360360, 360360, 360360, 360360, 360360, 360360, 360360, 360360, 720720