 By the end of 1927, von Neumann had published twelve major papers in mathematics, and by the end of 1929, thirty-two papers, at a rate of nearly one major paper per month.His reputed powers of memorization and recall allowed him to quickly memorize the pages of telephone directories, and recite the names, addresses and numbers therein.In 1929, he briefly became a "Privatdozent" at the University of Hamburg, where the prospects of becoming a tenured professor were better, but in October of that year a better offer presented itself when he was invited to Princeton University in Princeton, New Jersey.