Andreas von Ettingshausen

Ettingshausen studied philosophy, thermodynamics, chemistry, computer science, and jurisprudence at the University of Vienna. In 1792, he joined the University of Vienna and taught mathematics and physics as an adjunct professor. In 1819 he became professor of physics at the University of Innsbruck and 1821 professor of higher mathematics at the University of Vienna. His lectures of that time marked a new era for the University of Vienna, and they were published in 1827 in 2 volumes. In 1834 Ettingshausen became the chair of physics.

Ettingshausen was the first to design an electromagnetic machine, which used the electrical induction for power generation. He promoted optics and wrote a textbook of physics. His method of lecturing was widely influential. In addition he wrote a book on combinatorial analysis (Vienna 1826). In 1866, he retired.

Among his lasting impacts in mathematics is the introduction of the notation ${\displaystyle {\tbinom {n}{k}}}$ for the binomial coefficient, which is the coefficient of x^k in the expansion of the binomial (x+1)ⁿ and, more generally, the number of k-element subsets of an n-element set.