The Collatz g(z) fractal Close-up of the g(z) fractal at z = 1 Clip Source: en.wikipedia.org Lothar Collatz Lothar Collatz (July 6, 1910, Arnsberg , Westphalia ? September 26, 1990) was a German mathematician . In 1937 he posed the famous Collatz conjecture , which remains unsolved. Tags: mathematics zum Artikel...