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 A074532 #16 Sep 08 2022 08:45:07
%S A074532 3,11,45,197,897,4181,19785,94637,456417,2215781,10815225,53024477,
%T A074532 260921937,1287820181,6371967465,31591352717,156882923457,
%U A074532 780119453381,3883417004505,19348364759357,96466944316977,481235206811381
%N A074532 a(n) = 2^n + 4^n + 5^n.
%H A074532 Vincenzo Librandi, <a href="/A074532/b074532.txt">Table of n, a(n) for n = 0..200</a>
%H A074532 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (11,-38,40).
%F A074532 From _Mohammad K. Azarian_, Dec 27 2008: (Start)
%F A074532 G.f.: 1/(1-2*x) + 1/(1-4*x) + 1/(1-5*x).
%F A074532 E.g.f.: exp(2*x) + exp(4*x) + exp(5*x). (End)
%t A074532 Table[2^n + 4^n + 5^n, {n, 0, 20}]
%o A074532 (Magma) [2^n + 4^n + 5^n: n in [0..25]]; // _Vincenzo Librandi_, Jun 11 2011
%Y A074532 Cf. A001550, A001576, A034513, A001579, A074501 - A074580.
%K A074532 easy,nonn
%O A074532 0,1
%A A074532 _Robert G. Wilson v_, Aug 23 2002