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 A131716 #13 Dec 12 2023 09:15:47
%S A131716 0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,
%T A131716 8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1,
%U A131716 2,5,8,9,0,1,2,5,8,9,0,1,2,5,8,9,0,1
%N A131716 Period 6: repeat [0, 1, 2, 5, 8, 9].
%H A131716 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,0,0,0,1).
%F A131716 From _Wesley Ivan Hurt_, Jun 19 2016: (Start)
%F A131716 G.f.: x*(1+2*x+5*x^2+8*x^3+9*x^4)/(1-x^6).
%F A131716 a(n) = a(n-6) for n>5.
%F A131716 a(n) = (25 - 5*cos(n*Pi) - 10*cos(n*Pi/3) - 10*cos(2*n*Pi/3) - 14*sqrt(3)*sin(n*Pi/3) - 2*sqrt(3)*sin(2*n*Pi/3))/6. (End)
%p A131716 A131716:=n->[0, 1, 2, 5, 8, 9][(n mod 6)+1]: seq(A131716(n), n=0..100); # _Wesley Ivan Hurt_, Jun 19 2016
%t A131716 PadRight[{}, 200, {0, 1, 2, 5, 8, 9}] (* _Wesley Ivan Hurt_, Jun 19 2016 *)
%o A131716 (Magma) &cat[[0, 1, 2, 5, 8, 9]^^20]; // _Wesley Ivan Hurt_, Jun 19 2016
%Y A131716 Cf. A131711.
%K A131716 nonn,easy
%O A131716 0,3
%A A131716 _Paul Curtz_, Sep 14 2007