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 A210033 #5 Mar 30 2012 18:58:16 %S A210033 1,3,6,1,11,3,1,19,8,3,1,32,18,9,3,1,53,38,22,10,3,1,87,76,51,26,11,3, %T A210033 1,142,147,111,65,30,12,3,1,231,277,233,151,80,34,13,3,1,375,512,474, %U A210033 338,196,96,38,14,3,1,608,932,942,730,463,246,113,42,15,3,1 %N A210033 Triangle of coefficients of polynomials u(n,x) jointly generated with A210034; see the Formula section. %C A210033 For a discussion and guide to related arrays, see A208510. %F A210033 u(n,x)=u(n-1,x)+v(n-1,x)+1, %F A210033 v(n,x)=u(n-1,x)+x*v(n-1,x)+1, %F A210033 where u(1,x)=1, v(1,x)=1. %e A210033 First five rows: %e A210033 1 %e A210033 3 %e A210033 6....1 %e A210033 11...3...1 %e A210033 19...8...3...1 %e A210033 First three polynomials u(n,x): 1, 3, 6 + x. %t A210033 u[1, x_] := 1; v[1, x_] := 1; z = 16; %t A210033 u[n_, x_] := u[n - 1, x] + v[n - 1, x] + 1; %t A210033 v[n_, x_] := u[n - 1, x] + x*v[n - 1, x] + 1; %t A210033 Table[Expand[u[n, x]], {n, 1, z/2}] %t A210033 Table[Expand[v[n, x]], {n, 1, z/2}] %t A210033 cu = Table[CoefficientList[u[n, x], x], {n, 1, z}]; %t A210033 TableForm[cu] %t A210033 Flatten[%] (* A210033 *) %t A210033 Table[Expand[v[n, x]], {n, 1, z}] %t A210033 cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; %t A210033 TableForm[cv] %t A210033 Flatten[%] (* A210034 *) %Y A210033 Cf. A210034, A208510. %K A210033 nonn,tabf %O A210033 1,2 %A A210033 _Clark Kimberling_, Mar 16 2012