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 A153981 #21 Jan 03 2024 08:46:52
%S A153981 32,68,176,464,1220,3200,8384,21956,57488,150512,394052,1031648,
%T A153981 2700896,7071044,18512240,48465680,126884804,332188736,869681408,
%U A153981 2276855492,5960885072,15605799728,40856514116,106963742624,280034713760,733140398660
%N A153981 a(n) = 36*Fibonacci(2*n+1) - 4.
%H A153981 Vincenzo Librandi, <a href="/A153981/b153981.txt">Table of n, a(n) for n = 0..200</a>
%H A153981 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (4, -4, 1).
%F A153981 a(n) = 4*A153873(n) = 2*A153819(n).
%F A153981 a(n) = 5 (mod 9) = A010716(n) (mod 9).
%F A153981 a(n) = 3*a(n-1) - a(n-2) + 4.
%F A153981 a(n) = 4*a(n-1) - 4*a(n-2) + a(n-3).
%F A153981 a(n) = 3*a(n-1) - 3*a(n-3) + a(n-4).
%F A153981 G.f.: 4*(8 - 15*x + 8x^2)/((1-x)*(1 -3*x +x^2)). - _R. J. Mathar_, Jan 23 2009
%t A153981 36*Fibonacci[2*Range[0,30]+1]-4 (* or *) LinearRecurrence[{4,-4,1},{32,68,176},30] (* _Harvey P. Dale_, Jan 26 2013 *)
%o A153981 (Magma) [36*Fibonacci(2*n+1)-4: n in [0..30]]; // _Vincenzo Librandi_, Aug 07 2011
%K A153981 nonn,easy
%O A153981 0,1
%A A153981 _Paul Curtz_, Jan 04 2009
%E A153981 Edited and extended by _R. J. Mathar_ and _N. J. A. Sloane_, Jan 23 2009