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 A058920 #23 Dec 29 2024 21:01:23
%S A058920 1,10,65,250,697,1586,3145,5650,9425,14842,22321,32330,45385,62050,
%T A058920 82937,108706,140065,177770,222625,275482,337241,408850,491305,585650,
%U A058920 692977,814426,951185,1104490,1275625,1465922,1676761,1909570,2165825
%N A058920 a(n) = 2*n^4 + 2*n^3 + 3*n^2 + 2*n + 1.
%C A058920 On a 2n X (n^2 - n + 1) X n^2 cuboid (with n >= 3) there are six pairs of points with the maximum surface distance between them: the four pairs of opposite corners and the opposite pairs of points on the smallest faces 1 in from the midpoints of the shortest edges; this maximum surface distance is sqrt(a(n)).
%H A058920 Harry J. Smith, <a href="/A058920/b058920.txt">Table of n, a(n) for n = 0..500</a>
%H A058920 <a href="http://www.se16.info/js/cuboid.htm#Numerical">Source</a>
%H A058920 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F A058920 G.f.: (1+5*x+25*x^2+15*x^3+2*x^4)/(1-5*x+10*x^2-10*x^3+5*x^4-x^5). - _Colin Barker_, Jan 01 2012
%t A058920 Table[2n^4+2n^3+3n^2+2n+1,{n,0,40}] (* or *) LinearRecurrence[{5,-10,10,-5,1},{1,10,65,250,697},40] (* _Harvey P. Dale_, Dec 17 2017 *)
%o A058920 (PARI) a(n) = 2*n^4 + 2*n^3 + 3*n^2 + 2*n + 1 \\ _Harry J. Smith_, Jun 24 2009
%Y A058920 For n >= 2 the sequence is a subsequence of A007692.
%K A058920 nonn,easy
%O A058920 0,2
%A A058920 _Henry Bottomley_, Jan 11 2001