Breakdown (2018)

There's a great video with excellent visualizations by 3Blue1Brown that illustrates what's happening here: https://www.youtube.com/watch?v=851U557j6HE

Related:

Researchers thought this was a bug (Borwein integrals) [video] - https://news.ycombinator.com/item?id=33614213 - Nov 2022 (18 comments)

Breakdown: on Borwein integrals - https://news.ycombinator.com/item?id=17931336 - Sept 2018 (4 comments)

Two curious integrals and a graphic proof (2014) [pdf] - https://news.ycombinator.com/item?id=17883349 - Aug 2018 (1 comment)