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 A097136 #19 May 25 2018 12:56:06
%S A097136 1,4,10,25,64,166,433,1132,2962,7753,20296,53134,139105,364180,953434,
%T A097136 2496121,6534928,17108662,44791057,117264508,307002466,803742889,
%U A097136 2104226200,5508935710,14422580929,37758807076,98853840298,258802713817,677554301152
%N A097136 a(n) = 3*Fibonacci(2*n) + 1.
%C A097136 Binomial transform of A097135.
%H A097136 Colin Barker, <a href="/A097136/b097136.txt">Table of n, a(n) for n = 0..1000</a>
%H A097136 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4,-4,1)
%F A097136 G.f.: (1-2*x^2) / ((1-x)*(1-3*x+x^2)).
%F A097136 a(n) = 4*a(n-1) - 4*a(n-2) + a(n-3).
%F A097136 a(n) = 1+3((3+sqrt(5))/2)^n/sqrt(5)-3((3-sqrt(5))/2)^n/sqrt(5).
%F A097136 a(n) = A097132(2*n) = A097133(2*n).
%t A097136 Table[3*Fibonacci[2n]+1,{n,0,30}] (* or *) LinearRecurrence[{4,-4,1},{1,4,10},30] (* _Harvey P. Dale_, May 25 2018 *)
%o A097136 (PARI) Vec((1-2*x^2)/((1-x)*(1-3*x+x^2)) + O(x^30)) \\ _Colin Barker_, Nov 02 2016
%Y A097136 Cf. A000045.
%K A097136 nonn,easy
%O A097136 0,2
%A A097136 _Paul Barry_, Jul 26 2004