This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A338791 #64 Jun 09 2021 02:38:16
%S A338791 0,0,3,28,116,340,847,1832,3570,6440,10889,17518,26966,40002,57601,
%T A338791 80868,111186,150032,199147,260456,336080,428290,539709,673130,831436,
%U A338791 1018154,1237155,1492352,1787780,2129250,2521323,2969584,3479302,4056636,4707661,5438808
%N A338791 a(n) is the number of Platonic solids in three dimensions with all vertices (x,y,z) in the set {1,2,...,n}^3.
%C A338791 Dodecahedra and icosahedra with integer coordinates cannot be formed in Euclidean space (of any dimension) because pentagons with integer coordinates cannot be formed in Euclidean space, and both polyhedra contain a subset of vertices that form a pentagon. Therefore, this sequence counts the regular tetrahedra, cubes, and octahedra in the bounded cubic lattice.
%H A338791 Peter Kagey, <a href="/A338791/b338791.txt">Table of n, a(n) for n = 0..100</a>, based on the b-files for A098928, A103158, and A178797.
%H A338791 Eugen J. Ionascu and Andrei Markov, <a href="http://dx.doi.org/10.1016/j.jnt.2010.07.008">Platonic solids in Z^3</a>, Journal of Number Theory, Volume 131, Issue 1, January 2011, Pages 138-145.
%F A338791 a(n) = A098928(n) + 2*A103158(n-1) + A178797(n-1) for n >= 2.
%Y A338791 Cf. A098928 (cubes), A103158 (tetrahedra), A178797 (octahedra), A338323 (regular polygons).
%K A338791 nonn
%O A338791 0,3
%A A338791 _Peter Kagey_, Dec 05 2020