By Eric Kelsey LOS ANGELES, Jan 23 (Reuters) - Justin Timberlake's first single in five years - "Suit & Tie" - fell short of sales expectations for its first week and was kept from the top spot on the Billboard digital songs chart by a novelty rap act. "Suit & Tie," which features rapper Jay-Z, sold 314,000 downloads, according to figures released on Wednesday by Nielsen SoundScan.