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 A053536 #22 Sep 08 2022 08:45:00
%S A053536 1,8,112,1280,15616,186368,2240512,26869760,322502656,3869769728,
%T A053536 46438285312,557255229440,6687079530496,80244887257088,
%U A053536 962938915520512,11555265912504320,138663195245019136,1663958325760360448,19967499977843802112,239609999459247718400
%N A053536 Expansion of 1/((1+4*x)*(1-12*x)).
%D A053536 A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.
%H A053536 G. C. Greubel, <a href="/A053536/b053536.txt">Table of n, a(n) for n = 0..920</a>
%H A053536 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (8,48).
%F A053536 a(n) = (4^n/4)*(3^(n+1) + (-1)^n).
%F A053536 a(n) = 8*a(n-1) + 48*a(n-2), with a(0)=1, a(1)=8.
%F A053536 E.g.f.: (3*exp(12*x) + exp(-4*x))/4. - _G. C. Greubel_, May 16 2019
%F A053536 a(n) = 2^n*A053524(n+1). - _R. J. Mathar_, Mar 08 2021
%t A053536 LinearRecurrence[{8,48}, {1,8}, 30] (* _G. C. Greubel_, May 16 2019 *)
%o A053536 (PARI) Vec(1/((1+4*x)*(1-12*x)) + O(x^30)) \\ _Michel Marcus_, Dec 03 2014
%o A053536 (Magma) R<x>:=PowerSeriesRing(Integers(), 30); Coefficients(R!( 1/((1+4*x)*(1-12*x)) )); // _G. C. Greubel_, May 16 2019
%o A053536 (Sage) (1/((1+4*x)*(1-12*x))).series(x, 30).coefficients(x, sparse=False) # _G. C. Greubel_, May 16 2019
%o A053536 (GAP) a:=[1,8];; for n in [3..30] do a[n]:=8*a[n-1]+48*a[n-2]; od; a; # _G. C. Greubel_, May 16 2019
%Y A053536 Cf. A015518.
%K A053536 easy,nonn
%O A053536 0,2
%A A053536 _Barry E. Williams_, Jan 15 2000
%E A053536 Terms a(12) onward added by _G. C. Greubel_, May 16 2019