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 A213766 #16 Feb 19 2024 02:47:52 %S A213766 1,5,24,83,263,776,2201,6077,16488,44211,117615,311232,820641,2158645, %T A213766 5669096,14872483,38989367,102165928,267628569,700924525,1835493016, %U A213766 4806144675,12583939679,32947361088,86260987393,225840387941 %N A213766 Principal diagonal of the convolution array A213765. %H A213766 Clark Kimberling, <a href="/A213766/b213766.txt">Table of n, a(n) for n = 1..1000</a> %H A213766 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (5,-6,-3,6,1,-1). %F A213766 a(n) = 5*a(n-1) - 6*a(n-2) - 3*a(n-3) + 6*a(n-4) + a(n-5) - a(n-6). %F A213766 G.f.: f(x)/g(x), where f(x) = x*(1 + 5*x - 10*x^2) and g(x) = (1 - 3*x + 2*x^2 )^2. %t A213766 (See A213765.) %Y A213766 Cf. A213765, A213500. %K A213766 nonn,easy %O A213766 1,2 %A A213766 _Clark Kimberling_, Jun 21 2012