Sun Zhihong (, born October 16, 1965) is a Chinese mathematician, working primarily on number theory, combinatorics, and graph theory. Sun and his twin brother Sun Zhiwei proved a theorem about what are now known as the Wall–Sun–Sun primes that guided the search for counterexamples to Fermat's Last Theorem. External links Zhi-Hong Sun's homepage 1965 births Living people Mathematicians from Jiangsu 20th-century Chinese mathematicians 21st-century Chinese mathematicians Number theorists Academic staff of Huaiyin Normal University Scientists from Huai'an Educators from Huai'an Chinese twins