Paul Miller, 84, a lifelong newspaperman who was chairman of Gannett Co. and the Associated Press, died Wednesday at Good Samaritan Hospital in West Palm Beach, Fla., of complications from pneumonia, a hospital official said. As president, chief executive and chairman of Gannett, Mr. Miller oversaw the expansion of a small newspaper group into the nation's largest. He retired in 1980, after 33 years with Gannett. Mr. Miller was chairman of the Associated Press board from 1963 to 1977, the only former AP employee to hold that position. The Missouri native began his career at age 15.