The Philharmonic performs Sibelius’s late-Romantic Fifth Symphony, with a finale inspired by a silver-ribbon-like flight of 16 swans and, after exultant washes of sound, ending gloriously and affirmatively with six remarkable hammered chords. Leif Ove Andsnes (“a pianist of magisterial elegance, power, and insight”– The New York Times) is featured in Rachmaninoff’s brilliant Piano Concerto No. 4.