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Triangle of coefficients of polynomials u(n,x) jointly generated with A210214; see the Formula section.
3

%I #4 Mar 30 2012 18:58:16

%S 1,2,1,4,3,1,7,9,4,1,12,21,16,5,1,20,46,46,25,6,1,33,94,121,85,36,7,1,

%T 54,185,289,260,141,49,8,1,88,353,653,708,491,217,64,9,1,143,659,1409,

%U 1800,1499,847,316,81,10,1,232,1209,2939,4320,4229,2863,1366

%N Triangle of coefficients of polynomials u(n,x) jointly generated with A210214; see the Formula section.

%C Row sums: even-indexed Fibonacci numbers

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

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

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

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

%e First five rows:

%e 1

%e 2....1

%e 4....3....1

%e 7....9....4....1

%e 12...21...16...5...1

%e First three polynomials u(n,x): 1, 2 + x, 4 + 3x + 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] + 1;

%t v[n_, x_] := u[n - 1, x] + (x + 1)*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[%] (* A210213 *)

%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[%] (* A210214 *)

%Y Cf. A210214, A208510.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Mar 19 2012