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 A074609 #21 Jan 14 2024 02:30:25
%S A074609 2,11,73,539,4177,33011,262873,2099339,16783777,134237411,1073800873,
%T A074609 8590111739,68720008177,549757408211,4398051294073,35184386437739,
%U A074609 281475019757377,2251799942825411,18014398896902473,144115189238117339
%N A074609 a(n) = 3^n + 8^n.
%H A074609 G. C. Greubel, <a href="/A074609/b074609.txt">Table of n, a(n) for n = 0..1000</a>
%H A074609 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (11,-24).
%F A074609 From _Mohammad K. Azarian_, Jan 11 2009: (Start)
%F A074609 G.f.: 1/(1-3*x) + 1/(1-8*x).
%F A074609 E.g.f.: exp(3*x) + exp(8*x). (End)
%F A074609 a(n) = 11*a(n-1) - 24*a(n-2) with a(0)=2, a(1)=11. - _Vincenzo Librandi_, Jul 21 2010
%t A074609 Table[3^n + 8^n, {n, 0, 25}]
%t A074609 LinearRecurrence[{11,-24},{2,11},30] (* _Harvey P. Dale_, Mar 10 2015 *)
%o A074609 (Magma) [3^n+8^n: n in [0..30]]; // _G. C. Greubel_, Jan 14 2024
%o A074609 (SageMath) [3^n+9^n for n in range(31)] # _G. C. Greubel_, Jan 14 2024
%Y A074609 Cf. A000051, A007689, A034472, A034474, A034491, A052539, A062394.
%Y A074609 Cf. A062395, A062396, A063376, A063481, A074600..A074624.
%K A074609 easy,nonn
%O A074609 0,1
%A A074609 _Robert G. Wilson v_, Aug 25 2002