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Triangle of coefficients of polynomials u(n,x) jointly generated with A209171; see the Formula section.
3

%I #8 Apr 02 2012 03:38:36

%S 1,2,1,5,6,2,11,20,13,3,23,57,57,27,5,47,149,202,144,53,8,95,369,633,

%T 604,334,101,13,191,881,1831,2192,1618,733,188,21,383,2049,5007,7217,

%U 6665,4022,1544,344,34,767,4673,13135,22153,24570,18519,9461

%N Triangle of coefficients of polynomials u(n,x) jointly generated with A209171; see the Formula section.

%C Row n ends with A000045 (Fibonacci numbers).

%C Alternating row sums: 1,1,1,1,1,1,1,1,1,1,1,1,1,1,...

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

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

%F v(n,x)=(x+1)*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 5....6....2

%e 11...20...13...3

%e 23...57...57...27...5

%e First three polynomials v(n,x): 1, 2 + x, 5 + 6x + 2x^2.

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

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

%t v[n_, x_] := (x + 1)*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[%] (* A209170 *)

%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[%] (* A209171 *)

%Y Cf. A209171, A208510.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Mar 08 2012