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 A027117 #10 Oct 23 2019 20:33:10 %S A027117 16,59,155,352,738,1475,2861,5444,10232,19079,35395,65452,120786, %T A027117 222615,409965,754616,1388592,2554723,4699643,8644840,15901266, %U A027117 29247995,53796541,98948444,181995832,334743887,615691459,1132434708 %N A027117 a(n) = A027113(n, n+4). %F A027117 Conjectures from _Colin Barker_, Feb 20 2016: (Start) %F A027117 a(n) = 4*a(n-1)-5*a(n-2)+2*a(n-3)-a(n-4)+2*a(n-5)-a(n-6) for n>9. %F A027117 G.f.: x^4*(16-5*x-x^2-5*x^3+3*x^4) / ((1-x)^3*(1-x-x^2-x^3)). %F A027117 (End) %K A027117 nonn %O A027117 4,1 %A A027117 _Clark Kimberling_