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 A097804 #19 Sep 08 2022 08:45:14
%S A097804 9,33,153,753,3753,18753,93753,468753,2343753,11718753,58593753,
%T A097804 292968753,1464843753,7324218753,36621093753,183105468753,
%U A097804 915527343753,4577636718753,22888183593753,114440917968753,572204589843753,2861022949218753,14305114746093753
%N A097804 a(n) = 3*(2*5^n + 1).
%H A097804 Vincenzo Librandi, <a href="/A097804/b097804.txt">Table of n, a(n) for n = 0..1000</a>
%H A097804 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (6, -5).
%F A097804 a(0)=9, a(1)=33, a(n) = 6*a(n-1) - 5*a(n-2) for n > 1. - _Harvey P. Dale_, Dec 17 2012
%F A097804 G.f.: 3*(3-7*x)/((1-x)*(1-5*x)). - _Wesley Ivan Hurt_, Aug 16 2016
%p A097804 A097804:=n->3*(2*5^n+1): seq(A097804(n), n=0..30); # _Wesley Ivan Hurt_, Aug 16 2016
%t A097804 Table[3(2*5^n + 1), {n, 0, 20}] (* _Robert G. Wilson v_, Aug 26 2004 *)
%t A097804 LinearRecurrence[{6,-5}, {9,33}, 30] (* _Harvey P. Dale_, Dec 17 2012 *)
%t A097804 6*5^Range[0, 30] + 3 (* _Wesley Ivan Hurt_, Aug 16 2016 *)
%o A097804 (Magma) [3*(2*5^n+1) : n in [0..30]]; // _Wesley Ivan Hurt_, Aug 16 2016
%Y A097804 Cf. A097802, A097803.
%K A097804 nonn,easy
%O A097804 0,1
%A A097804 _George E. Antoniou_, Aug 25 2004
%E A097804 More terms from _Robert G. Wilson v_ and Mark Hudson (mrmarkhudson(AT)hotmail.com), Aug 26 2004