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 A135536 #13 Jan 08 2018 01:36:22
%S A135536 7,14,56,112,448,896,3584,7168,28672,57344,229376,458752,1835008,
%T A135536 3670016,14680064,29360128,117440512,234881024,939524096,1879048192,
%U A135536 7516192768,15032385536,60129542144,120259084288,481036337152
%N A135536 a(n) = 8*a(n-2), with a(0) = 7, a(1) = 14.
%H A135536 G. C. Greubel, <a href="/A135536/b135536.txt">Table of n, a(n) for n = 0..1000</a>
%H A135536 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,8).
%F A135536 a(n) = b(3*n) + b(3*n + 1) + b(3*n + 2), where b(n) = A135530(n) [previous name].
%F A135536 a(n) = 7 * abs(A094014(n)).
%F A135536 O.g.f.: 7*(1 + 2*x)/(1 - 8*x^2). - _R. J. Mathar_, Feb 23 2008
%F A135536 From _G. C. Greubel_, Oct 18 2016: (Start)
%F A135536 a(n) = (7/4)*( (2 + sqrt(2)) + (-1)^n*(2 - sqrt(2)) )*(sqrt(2))^(3*n).
%F A135536 a(n) = 8*a(n-2).
%F A135536 E.g.f.: (7/2)*( 2*cosh(2*sqrt(2)*x) + sqrt(2)*sinh(2*sqrt(2)*x) ). (End)
%t A135536 Table[(7/4)*( (2 + Sqrt[2]) + (-1)^n*(2 - Sqrt[2]) )*(Sqrt[2])^(3*n), {n,0,25}] (* or *) LinearRecurrence[{0,8},{7,14}, 25] (* _G. C. Greubel_, Oct 18 2016 *)
%o A135536 (PARI) a(n)=([0,1; 8,0]^n*[7;14])[1,1] \\ _Charles R Greathouse IV_, Oct 18 2016
%K A135536 nonn,easy
%O A135536 0,1
%A A135536 _Paul Curtz_, Feb 22 2008
%E A135536 More terms from _R. J. Mathar_, Feb 23 2008
%E A135536 New name from _G. C. Greubel_, Oct 18 2016