Prince Andrew apparently is not at it again. He is angrily denying any involvement with a 21-year-old British dancer who is part owner of a London dance club. The prince, who has often dated the kind of girls you don't bring home to mom, said this time someone's pulling a publicity stunt . . . The Foreign Student Service Council will dedicate its first permanent headquarters today at 2337 18th St. NW in honor of Alfred and Jean Friendly. Jean Friendly was one of the council's founders and her late husband, formerly the Pulitzer Prize-winning managing editor of The Washington Post, was a supporter of the council . . . Author Robert Ludlum and his former friend, author John Patrick, reached an out-of-court settlement yesterday on the suit Patrick brought accusing the spy novelist of stealing his idea for the book "The Road to Gandolfo" . . . In one of those weddings trendy New Yorkers love, actress Mariel Hemingway Sunday married Steve Crisman, the manager of the now "in" Hard Rock Cafe in New York . . . And now you'll be able to tell the difference, at least in London. The British Health Ministry has issued a report that the upper classes are tall and thin while the lower orders tend to be short and fat. It's probably because the upper classes can afford something other than British cooking. . .