John Lennon's singer son Sean teamed up with rockers The Flaming Lips to pay tribute to The Beatles with a cover of Lucy In the Sky with Diamonds during Thursday's (06Feb14) U.S. broadcast of the Late Show With David Letterman. The Tv gig was part of a week-long series of performances to mark the 50th anniversary of the Fab Four's first American Tv gig, which took place on 9 February, 1964 at New York's Ed Sullivan Theater, where the Letterman show tapes.