**Nicolaas de Bruijn** was a Dutch mathematician who worked in analysis, number theory, combinatorics and logic.

- De Bruijn, although still registered as an undergraduate at Leiden, became a full-time Assistant in the Department of Mathematics of the Technological University of Delft in September 1939.
- In addition to this full-time assistantship, de Bruijn continued his studies at Leiden until 1941.
- He undertook research on algebraic number theory and was awarded a doctorate on 26 March 1943 having submitted his thesis Over modulaire vormen van meer veranderlijken Ⓣ(Modular forms in several variables).
- Already before he had been awarded his doctorate, de Bruijn had begun publishing papers.
- For example he published On Steiner-Schläfli's hypocycloid (1940) which took a geometrical approach to ideas published by van der Woude earlier that year.
- In 1941 he published Ein Satz über schlichte Funktionen Ⓣ(A theorem on simple functions) followed by Common representative systems of two divisions of an aggregate into classes (1943) which generalised a theorem proved for finite sets by Denes König in 1916 and van der Waerden in 1927, then for infinite sets by König and Valko in 1925.
- In June 1944 de Bruijn became a Scientific Associate at Philips Research Laboratories in Eindhoven.
- He showed the breadth of his research interests with The electrostatic field of a point charge inside a cylinder, in connection with wave guide theory (written jointly with C J Bouwkamp) in 1947.
- He held this position at Philips Research Laboratories until October 1946 when he was appointed as a Professor in the Department of Mathematics of the Technological University of Delft.
- In September 1952 de Bruijn was appointed as Professor in the Department of Mathematics at the University of Amsterdam.
- Its purpose is to teach asymptotic methods by explaining a number of examples in every detail, so as to suit beginners who seriously want to acquire some technique in attacking asymptotic problems...
- It would be an excellent book to read in conjunction with a textbook or monograph on asymptotic expansions - if such a one existed: whether it can replace a textbook is a question which every reader will have to answer for himself.
- Substantial revisions have not been made.
- In September 1960 he became Professor in the Department of Mathematics at the Technological University of Eindhoven.
- He held this position until 1 August 1984 when he retired and was made Professor Emeritus.
- On returning to Eindhoven he renewed his links with the Philips Research Laboratories where he was made a Consultant in 1960, also a position he held until he retired in 1984.
- We have already indicated above some of the remarkable breadth in de Bruijn's mathematical interests.
- He lists his interests (on his website) as: Geometry, Number Theory, Classical and Functional Analysis, Applied Mathematics, Combinatorics, Computer Science, Logic, Mathematical Language, Brain Models.
- In the past decade he has been also working on the theories of the human brain.
- The language is so designed that it is incorrect to state a theorem without first "constructing" a proof of the theorem.
- Thus a computer verification of a body of text translated into AUTOMATH provides automated proof checking.
- De Bruijn has received, and continues to receive, many honours for his outstanding mathematical contributions.
- He lists on his website: Member Royal Netherlands Academy of Sciences since 1957; Invited Speaker at the International Congress of Mathematicians in Nice 1970; Ridder Nederlandse Leeuw (Knight in the Order of the Lion) 1981; Snellius Medal 1985 (This medal of the "Genootschap ter Bevordering van natuur-, genees-, en heelkunde" is awarded only once in 9 years for the whole field of mathematics, natural sciences and medicine.
- The work on the Automath project was the main motivation for this case); Honorary Member of the Dutch Mathematical Society (Wiskundig Genootschap) since 1988; AKZO Prize 1991; and in 2003 the Lifetime Achievement Award Nederlandse Vereniging v.

Born 9 July 1918, The Hague, The Netherlands. Died 17 February 2012, Nuenen, Netherlands.

View full biography at MacTutor

Origin Netherlands

**O’Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive