TWO FOR THE PRICE OF ONE: Lincoln Center’s yearlong cen tennial celebration of George Balanchine, founder of New York City Ballet, concentrated first, during the company’s winter season, on Balanchine’s heritage. But during the cur rent season, it has turned its attention on to his creativity and inspiration, which naturally involves new works. We have already had the excellent “Shambards,” by the compa ny’s resident choreographer, Christopher Wheeldon, and on Wednesday we have a world premiere by Balanchine’s suc cessor, the company’s artistic director, Peter Martins. In fact, we are to have two premieres – because although only one new ballet was originally announced, two are in fact on the agenda. The first ballet is “Chichester Psalms,” set to Leon ard Bernstein’s 1965 choral piece, in which City Ballet will be joined by the 100-voice Juilliard Choral Union. The second (you might say bonus ballet) is “Eros Piano,” devised to a 1989 score for piano and orchestra by John Adams. After the premieres on Wednesday, both ballets will be repeated – for this season – June 4, 5 and 6. New York State The ater, Lincoln Center, 65th Street at Broadway; (212) 870-5570.