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 A071397 #16 Feb 16 2025 08:32:46
%S A071397 0,21,83,186,330,516,743,1012,1321,1672,2065,2498,2973,3489,4047,4645,
%T A071397 5285,5967,6689,7453,8258,9105,9993,10922,11892,12904,13957,15051,
%U A071397 16186,17363,18581,19841,21141,22483,23866,25291,26757,28264,29812
%N A071397 Rounded total surface area of a regular dodecahedron with edge length n.
%D A071397 S. Selby, editor, CRC Basic Mathematical Tables, CRC Press, 1970, pp. 10-11.
%H A071397 Vincenzo Librandi, <a href="/A071397/b071397.txt">Table of n, a(n) for n = 0..10000</a>
%H A071397 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Dodecahedron.html">Dodecahedron</a>
%H A071397 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PlatonicSolid.html">Platonic Solid</a>
%F A071397 a(n) = round(3 * n^2 * sqrt(25 + 10*sqrt(5))).
%e A071397 a(4)=330 because round(3*4^2*sqrt(25 + 10*sqrt(5))) = round(48*6.88190...) = round(330.331...) = 330.
%t A071397 With[{c=3*Sqrt[25+10*Sqrt[5]]},Round[c*Range[0,40]^2]] (* _Harvey P. Dale_, Jul 06 2018 *)
%o A071397 (PARI) for(n=0,100,print1(round(3*n^2*sqrt(25+10*sqrt(5))),","))
%o A071397 (Magma) [Round(3 * n^2 * Sqrt(25+10*Sqrt(5))): n in [0..50]]; // _Vincenzo Librandi_, May 21 2011
%Y A071397 Cf. A070169 (tetrahedron), A033581 (cube), A071396 (octahedron), A071398 (icosahedron), A071401 (volume of dodecahedron).
%K A071397 easy,nonn
%O A071397 0,2
%A A071397 _Rick L. Shepherd_, May 28 2002