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 A126978 #37 Dec 11 2024 02:44:17
%S A126978 9977,10081,10185,10289,10393,10497,10601,10705,10809,10913,11017,
%T A126978 11121,11225,11329,11433,11537,11641,11745,11849,11953,12057,12161,
%U A126978 12265,12369,12473,12577,12681,12785,12889,12993,13097,13201,13305,13409,13513,13617,13721,13825
%N A126978 a(n) = 104*n + 9977.
%C A126978 Langton's Ant Superhighway, the start point (9977th iteration, J. Propp) and the period length for the Superhighway (104).
%H A126978 B. D. Swan, <a href="/A126978/b126978.txt">Table of n, a(n) for n = 0..10000</a>
%H A126978 C. Langton, <a href="http://dx.doi.org/10.1016/0167-2789(86)90237-X">Studying Artificial Life with Cellular Automata</a>, Physica D: Nonlinear Phenomena, Vol. 22, 1986, pp. 120-149.
%H A126978 Ed Pegg Jr, <a href="https://www.mathpuzzle.com/MAA/21-2D%20Turing%20Machines/mathgames_06_07_04.html">2D Turing Machines</a>, 2004.
%H A126978 James Propp, <a href="http://dx.doi.org/10.1007/BF03026614">Further Ant-ics</a>, Mathematical Intelligencer, Vol. 16, 1994, pp. 37-42.
%H A126978 P. Sarkar, <a href="https://doi.org/10.1145/349194.349202">A Brief History of Cellular Automata</a>, ACM Computing Surveys. Vol. 32, No. 1, Mar 01 2000, pp. 80-107.
%H A126978 S. Wolfram, <a href="https://www.wolframscience.com/nks/p185--turing-machines/">2D Turing Machines</a>.
%H A126978 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%F A126978 a(0)=9977, a(1)=10081, a(n) = 2*a(n-1) - a(n-2). - _Harvey P. Dale_, Dec 16 2011
%F A126978 G.f.: (9977 - 9873*x)/(1-x)^2. - _Vincenzo Librandi_, Sep 10 2015
%F A126978 E.g.f.: exp(x)*(9977 + 104*x). - _Elmo R. Oliveira_, Dec 08 2024
%t A126978 104*Range[0,40]+9977 (* or *) LinearRecurrence[{2,-1},{9977,10081},40] (* _Harvey P. Dale_, Dec 16 2011 *)
%t A126978 CoefficientList[Series[(9977 - 9873 x)/(1 - x)^2, {x, 0, 40}], x] (* _Vincenzo Librandi_, Sep 10 2015 *)
%o A126978 (Magma) [104*n + 9977: n in [0..40]]; // _Vincenzo Librandi_, Sep 10 2015
%o A126978 (PARI) a(n)=104*n+9977 \\ _Charles R Greathouse IV_, Oct 07 2015
%Y A126978 Cf. A102127, A102358, A102369, A126979, A126980.
%K A126978 easy,nonn
%O A126978 0,1
%A A126978 _Robert H Barbour_, Mar 20 2007, Jun 12 2007