Mariss Jansons, the chief conductor of this renowned orchestra, has long suffered from heart-related health problems, and announced a few weeks ago that he will be stepping down from his other appointment, with the Royal Concertgebouw Orchestra, next year. But he brings his Bavarian forces to Carnegie Hall for a marathon three concerts. The first, on Friday, features John Adams's "Slonimsky's Earbox," Strauss's "Don Juan" and Berlioz's "Symphonie Fantastique." On Saturday the redoubtable Mitsuko Uchida joins for Beethoven's Piano Concerto No. 4 on a concert that also includes Shostakovich's Symphony No. 5. The weekend is rounded out on Sunday with Ligeti's "Atmosphères," Brahms's Symphony No. 2 and Berg's Violin Concerto, with Gil Shaham as soloist.