Great article, great pictures - thanks. I knew of Euler's formula but no the history of it.

I think there is a typo near the end of the article: "you don't need to know at what angle *to* faces of a polyhedron meet".

## Typo

Great article, great pictures - thanks. I knew of Euler's formula but no the history of it.

I think there is a typo near the end of the article: "you don't need to know at what angle *to* faces of a polyhedron meet".