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 A074533 #26 Sep 08 2022 08:45:07
%S A074533 3,12,56,288,1568,8832,50816,296448,1745408,10340352,61515776,
%T A074533 366993408,2193563648,13127811072,78632615936,471258759168,
%U A074533 2825404940288,16943839444992,101628676407296,609634618441728
%N A074533 a(n) = 2^n + 4^n + 6^n.
%H A074533 Vincenzo Librandi, <a href="/A074533/b074533.txt">Table of n, a(n) for n = 0..200</a>
%H A074533 T. A. Gulliver, <a href="http://www.m-hikari.com/ijcms/ijcms-2012/37-40-2012/gulliverIJCMS37-40-2012.pdf">Sums of Powers of Integers Divisible by Three</a>, Int. J. Contemp. Math. Sciences, Vol. 7, 2012, no. 38, pp. 1895-1901. - From _N. J. A. Sloane_, Dec 22 2012
%H A074533 D. Suprijanto and Rusliansyah, <a href="http://dx.doi.org/10.12988/ams.2014.4140">Observation on Sums of Powers of Integers Divisible by Four</a>, Applied Mathematical Sciences, Vol. 8, 2014, no. 45, 2219-2226.
%H A074533 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (12,-44,48).
%F A074533 G.f.: 1/(1-2*x)+1/(1-4*x)+1/(1-6*x). E.g.f.: exp(2*x)+exp(4*x)+exp(6*x). - _Mohammad K. Azarian_, Dec 27 2008
%t A074533 Table[2^n + 4^n + 6^n, {n, 0, 20}]
%o A074533 (Magma) [2^n + 4^n + 6^n: n in [0..25]]; // _Vincenzo Librandi_, Jun 11 2011
%Y A074533 Cf. A001550, A001576, A034513, A001579, A074501-A074580.
%K A074533 easy,nonn
%O A074533 0,1
%A A074533 _Robert G. Wilson v_, Aug 23 2002