Gospel singer Marion Williams and public radio pioneer William H. Siemering are among 13 women and 18 men sharing in $ 9.2 million in so-called “genius grants” from the John D. and Catherine T. MacArthur Foundation.Williams, 65, has been recording since 1947 and has influenced artists in gospel, rock and soul music. She received a $ 374,000 grant. Siemering, a broadcasting consultant in Philadelphia, set the agenda for National Public Radio in 1970 when he wrote a mission statement that emphasized excellent writing, imaginative production and a conversational style. He said his $ 345,000 grant will enable him to train journalists and station managers in South Africa, where independent, community-based broadcasting will soon begin after years of government control of the airwaves. New York-based writer and critic Stanley Crouch said his $ 290,000 grant will enable him to work undistracted on a biography of saxophonist Charlie Parker and other projects.