Hans Heinrich Bürmann

Hans Heinrich Bürmann (died 21 June 1817, in Mannheim) was a German mathematician and teacher. He ran an "academy of commerce" in Mannheim since 1795 where he used to teach mathematics.^[1] He also served as a censor in Mannheim.^[1] He was nominated Headmaster of the Commerce Academy of the Grand Duchy of Baden in 1811. He did scientific research in the area of combinatorics and he contributed to the development of the symbolic language of mathematics. He discovered the generalized form of the Lagrange inversion theorem. He corresponded and published with Joseph Louis Lagrange and Carl Hindenburg.

Iterate function composition notation

The compositional notation ${\displaystyle f^{n}}$ for the ${\displaystyle n}$-th iterate ${\displaystyle f^{n}:=f\circ f^{n-1}=\overbrace {f\circ f\circ \dotsb \circ f} ^{n{\text{ times}}}}$ of function ${\displaystyle f}$ was originally introduced by Bürmann^{[citation needed][2][3]} and later independently suggested by John Frederick William Herschel in 1813.^[4][2][3]

See also

• Bürmann series
• Lagrange–Bürmann formula

References

1. Bürmann's biography (in German) from the Allgemeine Deutsche Biographie.
2. Herschel, John Frederick William (1820). "Part III. Section I. Examples of the Direct Method of Differences". A Collection of Examples of the Applications of the Calculus of Finite Differences. Cambridge, UK: Printed by J. Smith, sold by J. Deighton & sons. pp. 1–13 [5–6]. Archived from the original on 2020-08-04. Retrieved 2020-08-04. (NB. Inhere, Herschel refers to his 1813 work and mentions Hans Heinrich Bürmann's older work.)
3. Cajori, Florian (1952) [March 1929]. "§533. John Herschel's notation for inverse functions". A History of Mathematical Notations. Vol. 2 (3rd corrected printing of 1929 issue, 2nd ed.). Chicago, USA: Open court publishing company. pp. 176, 336, 346. ISBN 978-1-60206-714-1. ISBN 1-60206-714-7. Retrieved 2016-01-18. […] §533. John Herschel's notation for inverse functions, sin⁻¹ x, tan⁻¹ x, etc., was published by him in the Philosophical Transactions of London, for the year 1813. He says (p. 10): "This notation cos.⁻¹ e must not be understood to signify 1/cos. e, but what is usually written thus, arc (cos.=e)." He admits that some authors use cos.^m A for (cos. A)^m, but he justifies his own notation by pointing out that since d² x, Δ³ x, Σ² x mean dd x, ΔΔΔ x, ΣΣ x, we ought to write sin.² x for sin. sin. x, log.³ x for log. log. log. x. Just as we write d⁻ⁿ V=∫ⁿ V, we may write similarly sin.⁻¹ x=arc (sin.=x), log.⁻¹ x.=c^x. Some years later Herschel explained that in 1813 he used fⁿ(x), f⁻ⁿ(x), sin.⁻¹ x, etc., "as he then supposed for the first time. The work of a German Analyst, Burmann, has, however, within these few months come to his knowledge, in which the same is explained at a considerably earlier date. He[Burmann], however, does not seem to have noticed the convenience of applying this idea to the inverse functions tan⁻¹, etc., nor does he appear at all aware of the inverse calculus of functions to which it gives rise." Herschel adds, "The symmetry of this notation and above all the new and most extensive views it opens of the nature of analytical operations seem to authorize its universal adoption."^[a] […] (xviii+367+1 pages including 1 addenda page) (NB. ISBN and link for reprint of 2nd edition by Cosimo, Inc., New York, USA, 2013.)
4. Herschel, John Frederick William (1813) [1812-11-12]. "On a Remarkable Application of Cotes's Theorem". Philosophical Transactions of the Royal Society of London. 103 (Part 1). London: Royal Society of London, printed by W. Bulmer and Co., Cleveland-Row, St. James's, sold by G. and W. Nicol, Pall-Mall: 8–26 [10]. doi:10.1098/rstl.1813.0005. JSTOR 107384. S2CID 118124706.