20th-century Dutch mathematicians

Frederik Schuh (7 February 1875, Amsterdam – 6 January 1966, The Hague) was a Dutch mathematician.

Julius Wolff (18 April 1882 – 8 February 1945) was a Dutch-Jewish mathematician, known for the Denjoy–Wolff theorem and for his boundary version of the Schwarz lemma. With his family he was arrested in Utrecht by the Nazi occupation forces of the Netherlands on 8 March 1943 and transported to the Bergen-Belsen concentration camp on 13 September 1944, where he died of epidemic typhus on 8 February 1945, shortly before the camp was liberated.Wolff studied mathematics and physics at the University of Amsterdam, where he earned his doctorate in 1908 under Korteweg with thesis Dynamen, beschouwd als duale vectoren. From 1907 to 1917 he taught at secondary and grammar schools in Meppel, Middelburg, and Amsterdam. In 1917 Wolff was appointed Professor of differential calculus, theory of functions and higher algebra at the University of Groningen and in 1922 at the University of Utrecht. He was also a statistical advisor for the life insurance company (or co-operative distributive society) "Eigen Hulp," (a predecessor of AEGON) with offices at The Hague.

Nicolaas George Wijnand Henri Beeger (1884, in Utrecht – 1965, in Amsterdam) was a Dutch mathematician. His 1916 doctorate was on Dirichlet series. He worked for most of his life as a teacher, working on mathematics papers in his spare evenings. After his retirement as a teacher at 65, he began corresponding with many contemporary mathematicians and dedicated himself to his work. Tilburg University still holds biennial lectures entitled the Beeger lectures in his honour.
He is known for having proved that 3511 is a Wieferich prime in 1922 and for introducing the term Carmichael number in 1950.

Luitzen Egbertus Jan "Bertus" Brouwer (27 February 1881 – 2 December 1966) was a Dutch mathematician and philosopher who worked in topology, set theory, measure theory and complex analysis. He is seen as one of the founders of modern topology, in particular through his establishing the fixed-point theorem and the topological invariance of dimension.Brouwer also became a major figure in the philosophy of intuitionism, a constructivist school of mathematics which argues that math is a cognitive construct rather than a type of objective truth. This position led to the Brouwer–Hilbert controversy, in which Brouwer sparred with his formalist colleague David Hilbert. Brouwer's ideas were subsequently taken up by his student Arend Heyting and Hilbert's former student Hermann Weyl. In addition to his mathematical work, Brouwer also published the short philosophical tract Life, Art, and Mysticism (1905).