Editing Basel problem (section)

===History of this proof===
The proof goes back to [[Augustin Louis Cauchy]] (Cours d'Analyse, 1821, Note VIII). In 1954, this proof appeared in the book of [[Akiva Yaglom|Akiva]] and [[Isaak Yaglom]] "Nonelementary Problems in an Elementary Exposition". Later, in 1982, it appeared in the journal ''Eureka'',<ref>{{citation |last1=Ransford |first1=T J |title=An Elementary Proof of <math>\sum_{1}^{\infty}\frac{1}{n^2}=\frac{\pi^2}{6}</math> |journal=Eureka |date=Summer 1982 |volume=42 |issue=1 |pages=3–4|url=https://www.archim.org.uk/eureka/archive/Eureka-42.pdf  | archive-url = https://web.archive.org/web/20200610100509/https://www.archim.org.uk/eureka/archive/Eureka-42.pdf | archive-date = June 10, 2020}}</ref> attributed to John Scholes, but Scholes claims he learned the proof from [[Peter Swinnerton-Dyer]], and in any case he maintains the proof was "common knowledge at [[University of Cambridge|Cambridge]] in the late 1960s".<ref>{{citation
 | last1 = Aigner | first1 = Martin | author1-link = Martin Aigner
 | last2 = Ziegler | first2 = Günter M. | author2-link = Günter M. Ziegler
 | edition = 2nd
 | isbn = 9783662043158
 | page = 32
 | publisher = Springer
 | title = Proofs from THE BOOK
 | url = https://books.google.com/books?id=QETtCAAAQBAJ&pg=PA32
 | year = 2001}}; this anecdote is missing from later editions of this book, which replace it with earlier history of the same proof.</ref>