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 A209759 #6 Mar 30 2012 18:58:15 %S A209759 1,1,2,1,5,5,1,5,16,13,1,5,19,48,34,1,5,19,68,141,89,1,5,19,71,233, %T A209759 409,233,1,5,19,71,262,772,1175,610,1,5,19,71,265,948,2492,3349,1597, %U A209759 1,5,19,71,265,986,3354,7879,9482,4181,1,5,19,71,265,989,3641 %N A209759 Triangle of coefficients of polynomials u(n,x) jointly generated with A209760; see the Formula section. %C A209759 Limiting row: A001834 %C A209759 Coefficient of x^n in u(n,x): odd-indexed Fibonacci numbers %C A209759 Alternating row sums: 1,-1,1,-1,1,-1,1,-1,...; A033999 %C A209759 For a discussion and guide to related arrays, see A208510. %F A209759 u(n,x)=x*u(n-1,x)+(x+1)*v(n-1,x), %F A209759 v(n,x)=x*u(n-1,x)+2x*v(n-1,x)+1, %F A209759 where u(1,x)=1, v(1,x)=1. %e A209759 First five rows: %e A209759 1 %e A209759 1...2 %e A209759 1...5...5 %e A209759 1...5...16...13 %e A209759 1...5...19...48...34 %e A209759 First three polynomials u(n,x): 1, 1 + 2x, 1 + 5x + 5x^2. %t A209759 u[1, x_] := 1; v[1, x_] := 1; z = 16; %t A209759 u[n_, x_] := x*u[n - 1, x] + (x + 1)*v[n - 1, x]; %t A209759 v[n_, x_] := x*u[n - 1, x] + 2 x*v[n - 1, x] + 1; %t A209759 Table[Expand[u[n, x]], {n, 1, z/2}] %t A209759 Table[Expand[v[n, x]], {n, 1, z/2}] %t A209759 cu = Table[CoefficientList[u[n, x], x], {n, 1, z}]; %t A209759 TableForm[cu] %t A209759 Flatten[%] (* A209759 *) %t A209759 Table[Expand[v[n, x]], {n, 1, z}] %t A209759 cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; %t A209759 TableForm[cv] %t A209759 Flatten[%] (* A209760 *) %Y A209759 Cf. A209760, A208510. %K A209759 nonn,tabl %O A209759 1,3 %A A209759 _Clark Kimberling_, Mar 14 2012