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 A048513 #20 May 31 2023 15:44:10 %S A048513 1,82,263,665,1553,3505,7777,17089,37313,81089,175553,378817,815041, %T A048513 1748929,3743681,7995329,17039297,36241345,76939201,163053505, %U A048513 344981441,728760257,1537212353,3238002625,6811549633,14310965185 %N A048513 a(n) = T(8,n), array T given by A048505. %C A048513 n-th difference of a(n), a(n-1), ..., a(0) is (8^2, 9^2, 10^2, ...). %H A048513 Vincenzo Librandi, <a href="/A048513/b048513.txt">Table of n, a(n) for n = 0..2000</a> %H A048513 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (7,-18,20,-8). %F A048513 a(n) = (n^2+33*n+256) * 2^(n-2) - 63. - _Ralf Stephan_, Feb 05 2004 %F A048513 a(n) = 7*a(n-1)-18*a(n-2)+20*a(n-3)-8*a(n-4). - _Colin Barker_, Feb 25 2015 %F A048513 G.f.: (280*x^3-293*x^2+75*x+1) / ((x-1)*(2*x-1)^3). _Colin Barker_, Feb 25 2015 %o A048513 (Magma) [(n^2+33*n+256) * 2^(n-2) - 63: n in [0..30]]; // _Vincenzo Librandi_, Sep 26 2011 %o A048513 (PARI) Vec((280*x^3-293*x^2+75*x+1)/((x-1)*(2*x-1)^3) + O(x^100)) \\ _Colin Barker_, Feb 25 2015 %Y A048513 Cf. A048505. %K A048513 nonn,easy %O A048513 0,2 %A A048513 _Clark Kimberling_