There are multiple representations of pi as stated by the other commentor. One way of deriving it is given in the link, very elegant using the simple series for

There are multiple representations of pi as stated by the other commentor. One way of deriving it is given in the link, very elegant using the simple series formula. (Euler came up with it) [1]: https://golem.ph.utexas.edu/category/2020/08/eulers_continued_fraction_form.html https://golem.ph.utexas.edu/category/2020/08/eulers_continue...