There’s no mystery in why Hollywood keeps grinding out sequels: Put a number after a movie title these days and the line starts forming. But how many follow-ups can you name that equal or surpass a first-class original? Beyond The Godfather, Part II, I’m stumped. At best (the sequels to “Crocodile” Dundee, Rocky, Star Wars, Superman), we settle for more of the same without the exhilaration of discovery. At worst (the sequels to Rambo, Poltergeist, Jaws, Beverly Hills Cop), we find our goodwill so cynically exploited that we forget what we liked in the first place. Front and center this week are three new movies that try to dodge the sequel trap.