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 A154514 #32 Sep 08 2022 08:45:40
%S A154514 577,2449,5617,10081,15841,22897,31249,40897,51841,64081,77617,92449,
%T A154514 108577,126001,144721,164737,186049,208657,232561,257761,284257,
%U A154514 312049,341137,371521,403201,436177,470449,506017,542881,581041,620497,661249
%N A154514 a(n) = 648*n^2 - 72*n + 1.
%C A154514 The identity (648*n^2 - 72*n + 1)^2 - (9*n^2 - n)*(216*n - 12)^2 = 1 can be written as a(n)^2 - A154516(n)*A154518(n)^2 = 1. This is the case s=3 of the identity (8*n^2*s^4 - 8*n*s^2 + 1)^2 - (n^2*s^2 - n)*(8*n*s^3 - 4*s)^2 = 1. - _Vincenzo Librandi_, Jan 30 2012
%H A154514 Vincenzo Librandi, <a href="/A154514/b154514.txt">Table of n, a(n) for n = 1..10000</a>
%H A154514 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A154514 G.f.: x*(-577 - 718*x - x^2)/(x-1)^3. - _Harvey P. Dale_, Apr 22 2011
%F A154514 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3). - _Vincenzo Librandi_, Jan 30 2012
%t A154514 Table[648n^2-72n+1,{n,50}] (* _Harvey P. Dale_, Apr 22 2011 *)
%o A154514 (PARI) a(n)=648*n^2-72*n+1 \\ _Charles R Greathouse IV_, Dec 27 2011
%o A154514 (Magma) I:=[577, 2449, 5617]; [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 30 2012
%Y A154514 Cf. A154516, A154518.
%K A154514 nonn,easy
%O A154514 1,1
%A A154514 _Vincenzo Librandi_, Jan 11 2009