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 A210287 #5 Mar 30 2012 18:58:16 %S A210287 1,3,1,6,6,1,11,18,10,1,19,45,41,15,1,32,100,130,80,21,1,53,208,352, %T A210287 310,141,28,1,87,413,866,994,652,231,36,1,142,794,1991,2828,2429,1253, %U A210287 358,45,1,231,1490,4358,7391,7871,5348,2248,531,55,1,375,2745 %N A210287 Triangle of coefficients of polynomials v(n,x) jointly generated with A209999; see the Formula section. %C A210287 Column 1: -2+F(n+3), where F=000045 (Fibonacci numbers) %C A210287 Row sums: A003462 %C A210287 Alternating row sums: 1,2,1,2,1,2,1,2,1,2,1,2,1,2,... %C A210287 For a discussion and guide to related arrays, see A208510. %F A210287 u(n,x)=x*u(n-1,x)+(x+1)*v(n-1,x)+1, %F A210287 v(n,x)=u(n-1,x)+(x+1)*v(n-1,x)+1, %F A210287 where u(1,x)=1, v(1,x)=1. %e A210287 First five rows: %e A210287 1 %e A210287 3....1 %e A210287 6....6....1 %e A210287 11...18...10...1 %e A210287 19...45...41...15...1 %e A210287 First three polynomials v(n,x): 1, 3 + x , 6 + 6x + x^2. %t A210287 u[1, x_] := 1; v[1, x_] := 1; z = 16; %t A210287 u[n_, x_] := x*u[n - 1, x] + (x + 1)*v[n - 1, x] + 1; %t A210287 v[n_, x_] := u[n - 1, x] + (x + 1)*v[n - 1, x] + 1; %t A210287 Table[Expand[u[n, x]], {n, 1, z/2}] %t A210287 Table[Expand[v[n, x]], {n, 1, z/2}] %t A210287 cu = Table[CoefficientList[u[n, x], x], {n, 1, z}]; %t A210287 TableForm[cu] %t A210287 Flatten[%] (* A209999 *) %t A210287 Table[Expand[v[n, x]], {n, 1, z}] %t A210287 cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; %t A210287 TableForm[cv] %t A210287 Flatten[%] (* A210287 *) %Y A210287 Cf. A209999, A208510. %K A210287 nonn,tabl %O A210287 1,2 %A A210287 _Clark Kimberling_, Mar 23 2012