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 A083595 #26 Sep 08 2022 08:45:10
%S A083595 1,6,8,20,36,76,148,300,596,1196,2388,4780,9556,19116,38228,76460,
%T A083595 152916,305836,611668,1223340,2446676,4893356,9786708,19573420,
%U A083595 39146836,78293676,156587348,313174700,626349396,1252698796,2505397588
%N A083595 a(n) = (7*2^n - 4(-1)^n)/3.
%C A083595 Binomial transform of A083594.
%H A083595 Vincenzo Librandi, <a href="/A083595/b083595.txt">Table of n, a(n) for n = 0..238</a>
%H A083595 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1,2).
%F A083595 a(n) = (7*2^n - 4(-1)^n)/3 .
%F A083595 G.f.: (1+5*x)/((1-2*x)*(1+x)).
%F A083595 E.g.f.: (7*exp(2*x) - 4*exp(-x))/3.
%t A083595 LinearRecurrence[{1,2},{1,6},40] (* _Harvey P. Dale_, Aug 13 2019 *)
%o A083595 (Magma) [(7*2^n-4*(-1)^n)/3: n in [0..40]]; // _Vincenzo Librandi_, Apr 28 2011
%Y A083595 Cf. A082541.
%K A083595 easy,nonn
%O A083595 0,2
%A A083595 _Paul Barry_, May 02 2003