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Triangle of coefficients of polynomials u(n,x) jointly generated with A209576; see the Formula section.
3

%I #5 Mar 30 2012 18:58:15

%S 1,1,1,1,5,1,1,5,15,1,1,5,23,37,1,1,5,23,89,83,1,1,5,23,105,295,177,1,

%T 1,5,23,105,447,873,367,1,1,5,23,105,479,1721,2383,749,1,1,5,23,105,

%U 479,2121,6015,6137,1515,1,1,5,23,105,479,2185,8847,19369,15143

%N Triangle of coefficients of polynomials u(n,x) jointly generated with A209576; see the Formula section.

%C For a discussion and guide to related arrays, see A208510.

%F u(n,x)=x*u(n-1,x)+v(n-1,x),

%F v(n,x)=2x*u(n-1,x)+2x*v(n-1,x)+1,

%F where u(1,x)=1, v(1,x)=1.

%e First five rows:

%e 1

%e 1...1

%e 1...5...1

%e 1...5...15...1

%e 1...5...23...37...1

%e First three polynomials v(n,x): 1, 1 + x, 1 + 5x + x^2.

%t u[1, x_] := 1; v[1, x_] := 1; z = 16;

%t u[n_, x_] := x*u[n - 1, x] + v[n - 1, x];

%t v[n_, x_] := 2 x*u[n - 1, x] + 2 x*v[n - 1, x] + 1;

%t Table[Expand[u[n, x]], {n, 1, z/2}]

%t Table[Expand[v[n, x]], {n, 1, z/2}]

%t cu = Table[CoefficientList[u[n, x], x], {n, 1, z}];

%t TableForm[cu]

%t Flatten[%] (* A209575 *)

%t Table[Expand[v[n, x]], {n, 1, z}]

%t cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];

%t TableForm[cv]

%t Flatten[%] (* A209576 *)

%Y Cf. A209576, A208510.

%K nonn,tabl

%O 1,5

%A _Clark Kimberling_, Mar 11 2012