Piano man Ben Folds has never been shy about collaborating with others. From his early days leading the power-pop Ben Folds Five, working with Captain Kirk himself, William Shatner as a producer, arranger, and backup musician, forming a side project called the Bens with Ben Lee and Ben Kweller, and even releasing an a cappella album with college university ensembles, the oddball songwriter enjoys thinking outside the box when it comes to joint ventures. His latest album, “Lonely Avenue,” follows the same inventiveness, tapping author Nick Hornby (“High Fidelity,” “About a Boy”) to write lyrics that Folds would then combine with music (a deluxe edition of the record comes with a hardbound 152-page book featuring four of Hornby’s short stories and photographs by Guggenheim fellow Joel Meyerowitz). Pairing his signature snarky cynicism with heartfelt sentiment, Folds is scheduled to perform the National on Thursday, April 14 at 8 p.m. $30.