Impressionist, modern and contemporary art with an estimated value of least $1.6 billion will be offered at Christie’s, Sotheby’s and Phillips. The value of these consignments, which include works by Francis Bacon, Andy Warhol, Fernand Leger and Franz Kline, as well as, incongruously, a Ferrari racecar, represents an increase of more than 46 percent over the equivalent auctions last November.