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 A136254 #10 Oct 19 2022 08:06:21
%S A136254 4,6,8,12,20,34,56,88,132,190,264,356,468,602,760,944,1156,1398,1672,
%T A136254 1980,2324,2706,3128,3592,4100,4654,5256,5908,6612,7370,8184,9056,
%U A136254 9988,10982,12040,13164,14356
%N A136254 Generator for the finite sequence A053016.
%H A136254 G. C. Greubel, <a href="/A136254/b136254.txt">Table of n, a(n) for n = 0..1000</a>
%H A136254 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F A136254 a(n) = n^3/3 - n^2 + 8n/3 + 4.
%F A136254 G.f.: (8*x^2 - 10*x + 4)/(x^4 - 4*x^3 + 6*x^2 - 4*x + 1). - _Alexander R. Povolotsky_, Mar 31 2008
%F A136254 From _G. C. Greubel_, Feb 23 2017: (Start)
%F A136254 E.g.f.: (1/3)*(12 + 6*x + x^3)*exp(x).
%F A136254 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)
%t A136254 CoefficientList[Series[(8*x^2 - 10*x + 4)/(x^4 - 4*x^3 + 6*x^2 - 4*x + 1), {x, 0, 50}], x] (* _G. C. Greubel_, Feb 23 2017 *)
%t A136254 LinearRecurrence[{4,-6,4,-1},{4,6,8,12},40] (* _Harvey P. Dale_, Jul 23 2018 *)
%o A136254 (PARI) x='x+O('x^50); Vec((8*x^2 - 10*x + 4)/(x^4 - 4*x^3 + 6*x^2 - 4*x + 1)) \\ _G. C. Greubel_, Feb 23 2017
%Y A136254 Cf. A053016.
%K A136254 nonn,easy
%O A136254 0,1
%A A136254 _Rolf Pleisch_, Mar 17 2008