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 A048481 #23 Oct 31 2023 15:43:27
%S A048481 1,3,9,27,77,207,529,1299,3093,7191,16409,36891,81949,180255,393249,
%T A048481 852003,1835045,3932199,8388649,17825835,37748781,79691823,167772209,
%U A048481 352321587,738197557,1543503927,3221225529,6710886459,13958643773,28991029311,60129542209
%N A048481 a(n) = T(0,n) + T(1,n-1) + ... + T(n,0), array T given by A048472.
%H A048481 Colin Barker, <a href="/A048481/b048481.txt">Table of n, a(n) for n = 0..1000</a>
%H A048481 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (6,-13,12,-4).
%F A048481 Row sums of triangle A134397. Also, binomial transform of A048166. - _Gary W. Adamson_, Oct 23 2007
%F A048481 a(n) = 6*a(n-1)-13*a(n-2)+12*a(n-3)-4*a(n-4). - _Colin Barker_, Dec 04 2014
%F A048481 G.f.: (4*x^2-3*x+1) / ((x-1)^2*(2*x-1)^2). - _Colin Barker_, Dec 04 2014
%F A048481 a(n) = 2^(n+1)*(n-2) + 2*n + 5. - _Christian Krause_, Oct 31 2023
%t A048481 LinearRecurrence[{6,-13,12,-4},{1,3,9,27},40] (* _Harvey P. Dale_, Aug 13 2015 *)
%o A048481 (PARI) Vec((4*x^2-3*x+1)/((x-1)^2*(2*x-1)^2) + O(x^100)) \\ _Colin Barker_, Dec 04 2014
%Y A048481 Partial sums of A048495.
%Y A048481 Cf. A134397, A048166.
%K A048481 nonn,easy
%O A048481 0,2
%A A048481 _Clark Kimberling_
%E A048481 Corrected by _T. D. Noe_, Nov 08 2006