John Carlos Baez on Nostr: The rhombicosidodecahedron is an Archimedean solid with 12 pentagons, 20 equilateral ...
The rhombicosidodecahedron is an Archimedean solid with 12 pentagons, 20 equilateral triangles, and 30 squares as faces. You can draw it with all its vertices having coordinates of the form a + b√5 with a,b rational. If you replace √5 by -√5, you get something kind of wonderful! The squares stay square. The triangles stay equilateral triangles. But the pentagons turn into pentagrams!
Here I've only drawn the pentagrams, because it gets a bit messy otherwise.
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Published at
2026-05-29 12:55:57 UTCEvent JSON
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