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 A157326 #21 Sep 08 2022 08:45:41
%S A157326 10657,42049,94177,167041,260641,374977,510049,665857,842401,1039681,
%T A157326 1257697,1496449,1755937,2036161,2337121,2658817,3001249,3364417,
%U A157326 3748321,4152961,4578337,5024449,5491297,5978881,6487201,7016257
%N A157326 a(n) = 10368*n^2 + 288*n + 1.
%C A157326 The identity (10368*n^2 + 288*n + 1)^2 - (36*n^2 + n)*(1728*n + 24)^2 = 1 can be written as a(n)^2 - A157324(n)*A157325(n)^2 = 1 (see also second part of the comment at A157324). - _Vincenzo Librandi_, Jan 26 2012
%H A157326 Vincenzo Librandi, <a href="/A157326/b157326.txt">Table of n, a(n) for n = 1..10000</a>
%H A157326 Vincenzo Librandi, <a href="http://mathforum.org/kb/message.jspa?messageID=5785989&tstart=0">X^2-AY^2=1</a>
%H A157326 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A157326 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - _Vincenzo Librandi_, Jan 26 2012
%F A157326 G.f.: x*(-x^2 - 10078*x - 10657)/(x-1)^3. - _Vincenzo Librandi_, Jan 26 2012
%F A157326 a(n) = 2*A017533(6n)^2 - 1. - _Bruno Berselli_, Jan 29 2012
%t A157326 LinearRecurrence[{3,-3,1},{10657,42049,94177},50] (* _Vincenzo Librandi_, Jan 26 2012 *)
%o A157326 (Magma) I:=[10657, 42049, 94177]; [n le 3 select I[n] else 3*Self(n-1)-3*Self(n-2)+1*Self(n-3): n in [1..50]]; // _Vincenzo Librandi_, Jan 26 2012
%o A157326 (PARI) for(n=1, 22, print1(10368*n^2 + 288*n + 1", ")); \\ _Vincenzo Librandi_, Jan 26 2012
%Y A157326 Cf. A157324, A157325.
%K A157326 nonn,easy
%O A157326 1,1
%A A157326 _Vincenzo Librandi_, Feb 27 2009