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 A017030 #21 May 07 2024 06:47:41
%S A017030 16,121,324,625,1024,1521,2116,2809,3600,4489,5476,6561,7744,9025,
%T A017030 10404,11881,13456,15129,16900,18769,20736,22801,24964,27225,29584,
%U A017030 32041,34596,37249,40000,42849,45796
%N A017030 a(n) = (7*n + 4)^2.
%H A017030 Vincenzo Librandi, <a href="/A017030/b017030.txt">Table of n, a(n) for n = 0..10000</a>
%H A017030 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A017030 a(n) = A017029(n)^2. - _Michel Marcus_, Nov 11 2013
%F A017030 Sum{n>=0} 1/a(n) = psi'(4/7)/49 = 0.080438723... - _R. J. Mathar_, May 07 2024
%p A017030 A017030:=n->(7*n+4)^2; seq(A017030(n), n=0..100); # _Wesley Ivan Hurt_, Nov 11 2013
%t A017030 Table[(7n+4)^2, {n,0,100}] (* _Wesley Ivan Hurt_, Nov 11 2013 *)
%t A017030 LinearRecurrence[{3,-3,1},{16,121,324},40] (* _Harvey P. Dale_, May 25 2019 *)
%o A017030 (Magma) [(7*n+4)^2: n in [0..40] ]; // _Vincenzo Librandi_, Jul 16 2011
%o A017030 (PARI) a(n)=(7*n+4)^2 \\ _Charles R Greathouse IV_, Jun 17 2017
%K A017030 nonn,easy
%O A017030 0,1
%A A017030 _N. J. A. Sloane_