Vadim Georgievich Vizing (Russian: Вади́м Гео́ргиевич Визинг, Ukrainian: Вадим Георгійович Візінг; 25 March 1937 – 23 August 2017)[1] was a Soviet and Ukrainian mathematician known for his contributions to graph theory, and especially for Vizing's theorem stating that the edges of any simple graph with maximum degree Δ can be colored with at most Δ + 1 colors.