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 A074548 #20 May 26 2024 02:19:47
%S A074548 3,13,61,307,1633,9043,51481,298507,1751713,10359523,61573801,
%T A074548 367168507,2194090993,13129397203,78637382521,471273075307,
%U A074548 2825447921473,16943968454083,101629063565641,609635780178907
%N A074548 a(n) = 3^n + 4^n + 6^n.
%H A074548 Vincenzo Librandi, <a href="/A074548/b074548.txt">Table of n, a(n) for n = 0..200</a>
%H A074548 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (13,-54,72).
%F A074548 From _Mohammad K. Azarian_, Dec 28 2008: (Start)
%F A074548 G.f.: 1/(1-3*x) + 1/(1-4*x) + 1/(1-6*x).
%F A074548 E.g.f.: exp(3*x) + exp(4*x) + exp(6*x). (End)
%F A074548 a(n) = 13*a(n-1) - 54*a(n-2) + 72*a(n-3).
%t A074548 Table[3^n + 4^n + 6^n, {n, 0, 21}]
%t A074548 LinearRecurrence[{13,-54,72},{3,13,61},30] (* _Harvey P. Dale_, Dec 21 2022 *)
%o A074548 (Magma) [3^n + 4^n + 6^n: n in [0..30]]; // _Vincenzo Librandi_, Jun 13 2011
%Y A074548 Cf. A001550, A001576, A034513, A001579, A074501 - A074580.
%K A074548 easy,nonn
%O A074548 0,1
%A A074548 _Robert G. Wilson v_, Aug 23 2002