Ronald Graham (1935–2020) is regarded as "one of the principal architects of the rapid worldwide development of discrete mathematics in recent years," as stated in the citation for the Leroy P. Steele Prize, awarded by the American Mathematical Society, which he received in 2003 for lifetime achievement.
After a chaotic childhood and education, he enlisted in the Air Force for four years before returning to higher education. His 1962 dissertation was entitled On finite sums of rational numbers. He then worked at Bell Labs, at the time a veritable hotbed of mathematicians. In 1999, he joined the University of California. Somewhat like Erdős, he worked in every field, from number theory—particularly Egyptian fractions—to discrete geometry, via Ramsey theory and graph theory. Many concepts and theorems bear his name. It was Graham who introduced the notion of an Erdős number.
Alongside his work as a mathematician, Ronald Graham was also a champion juggler and developed a mathematical theory of the art. From the age of 15, he practised almost every day and could easily juggle six balls, occasionally even seven—a fairly rare feat! To earn money while completing his dissertation, he also worked as a professional trampolinist.
