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 A113441 #13 Jul 05 2024 14:27:15
%S A113441 1,3,12,50,212,905,3872,16576,70968,303832,1300737,5568473,23838453,
%T A113441 102051167,436874885,1870233780,8006350999,34274673894,146727674181,
%U A113441 628131735844,2688991567300,11511399994065,49279563214531
%N A113441 Second row of A113439.
%H A113441 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (9, -28, 38, -20, 1).
%F A113441 a(n) = A113439(4*n+1).
%F A113441 a(n) = 9*a(n-1) - 28*a(n-2) + 38*a(n-3) - 20*a(n-4) + a(n-5).
%F A113441 G.f.: -(1-6*x+13*x^2-12*x^3+4*x^4)/(-1+9*x-28*x^2+38*x^3-20*x^4+x^5).
%t A113441 LinearRecurrence[{9,-28,38,-20,1},{1,3,12,50,212},30] (* _Harvey P. Dale_, Apr 06 2013 *)
%t A113441 CoefficientList[Series[-(1 - 6*x + 13*x^2 - 12*x^3 + 4*x^4)/(-1 + 9*x - 28*x^2 + 38*x^3 - 20*x^4 + x^5), {x,0,50}], x] (* _G. C. Greubel_, Mar 11 2017 *)
%o A113441 (PARI) x='x+O('x^50); Vec(-(1-6*x+13*x^2-12*x^3+4*x^4)/(-1+9*x-28*x^2+38*x^3-20*x^4+x^5)) \\ _G. C. Greubel_, Mar 11 2017
%Y A113441 Cf. A113439.
%K A113441 nonn,easy
%O A113441 0,2
%A A113441 _Floor van Lamoen_, Nov 04 2005