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 A160413 #20 Feb 02 2024 09:02:10
%S A160413 2,1,7,2,13,3,19,4,25,5,31,6,37,7,43,8,49,9,55,10,61,11,67,12,73,13,
%T A160413 79,14,85,15,91,16,97,17,103,18,109,19,115,20,121,21,127,22,133,23,
%U A160413 139,24,145,25,151,26,157,27,163,28,169,29,175,30,181,31,187,32,193
%N A160413 a(n) = A160411(n+1)/4.
%H A160413 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,2,0,-1).
%F A160413 G.f.: x*(x^4 + 3*x^2 + x+2) / ((x-1)^2*(x+1)^2). - _Colin Barker_, Mar 04 2013
%F A160413 From _Colin Barker_, Apr 06 2013: (Start)
%F A160413 a(n) = -1 + (-1)^n - (1/4)*(-7 + 5*(-1)^n)*n for n > 1.
%F A160413 a(n) = 2*a(n-2) - a(n-4) for n > 5. (End)
%t A160413 LinearRecurrence[{0, 2, 0, -1}, {2, 1, 7, 2, 13}, 100] (* _Amiram Eldar_, Feb 02 2024 *)
%Y A160413 Cf. A152978, A160117 A160411, A160417.
%K A160413 nonn,easy
%O A160413 1,1
%A A160413 _Omar E. Pol_, Jun 13 2009
%E A160413 More terms from _Colin Barker_, Apr 06 2013
%E A160413 More terms from _Amiram Eldar_, Feb 02 2024