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 A165232 #19 Mar 19 2024 03:27:47
%S A165232 1,9,153,2673,46737,817209,14289129,249849441,4368687777,76387735017,
%T A165232 1335661040313,23354409110481,408358414625841,7140261781270809,
%U A165232 124849486331241993
%N A165232 a(0)=1, a(1)=9, a(n) = 18*a(n-1) - 9*a(n-2) for n>1.
%H A165232 Paolo Xausa, <a href="/A165232/b165232.txt">Table of n, a(n) for n = 0..500</a>
%H A165232 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (18,-9)
%F A165232 G.f.: (1-9*x)/(1-18*x+9*x^2).
%t A165232 LinearRecurrence[{18,-9},{1,9},25] (* _Paolo Xausa_, Jan 04 2024 *)
%K A165232 nonn,easy
%O A165232 0,2
%A A165232 _Philippe Deléham_, Sep 09 2009