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 A054603 #21 Jul 11 2021 04:42:14
%S A054603 0,4,24,96,280,660,1344,2464,4176,6660,10120,14784,20904,28756,38640,
%T A054603 50880,65824,83844,105336,130720,160440,194964,234784,280416,332400,
%U A054603 391300,457704,532224,615496,708180,810960,924544,1049664
%N A054603 a(n) = Sum_{d|4} phi(d)*n^(4/d).
%H A054603 Seiichi Manyama, <a href="/A054603/b054603.txt">Table of n, a(n) for n = 0..10000</a>
%H A054603 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F A054603 a(n) = n^4 + n^2 + 2n.
%F A054603 G.f.: -4*x*(4*x^2+x+1)/(x-1)^5. [_Colin Barker_, Dec 21 2012]
%t A054603 LinearRecurrence[{5,-10,10,-5,1},{0,4,24,96,280},40] (* _Harvey P. Dale_, Nov 29 2015 *)
%Y A054603 Row n=4 of A185651.
%K A054603 nonn,easy
%O A054603 0,2
%A A054603 _N. J. A. Sloane_, Apr 16 2000