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December 28
Why are Reeve tetrahedra skewed?
Reeve tetrahedra showing that Pick's theorem does not apply in over two dimensions
Choose , so the four vertices are lattice points, having positions and Then, next to these four, also the lattice point lies on the surface of the tetrahedron. --Lambiam19:57, 28 December 2022 (UTC)[reply]
To clarify a bit for who aren't familiar with them, the point of the Reeve tetrahedra is to show there is no three dimensional version of Pick's theorem. If the fourth vertex is (0, 0, r) then the number of lattice points on the surface vary with r, and that invalidates the example. Reeve tetrahedra have the same number of interior lattice points (0), face lattice points (0) and edge lattice points (0), the number of vertices is the same (4), and vertices are lattice points, but the volumes are different. --RDBury (talk) 00:01, 29 December 2022 (UTC)[reply]
Also the text at the bottom is (1) in a font-size that is almost illegibly small at the size the image is displayed in the article, and (2) is largely pointless (all Reeve tetrahedra have i = 0 and b = 4, and the volume is related to r in a trivial way). I suggest removing those lines and changing the caption to read "Reeve tetrahedra for r = 1, 2, and 3" or something similar. 100.36.106.199 (talk) 16:29, 31 December 2022 (UTC)[reply]