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Triangle of coefficients of polynomials u(n,x) jointly generated with A207632; see the Formula section.
3

%I #5 Mar 30 2012 18:58:13

%S 1,2,4,2,7,6,2,12,15,8,2,20,33,25,10,2,33,68,66,37,12,2,54,134,159,

%T 113,51,14,2,88,256,359,309,176,67,16,2,143,478,774,781,536,257,85,18,

%U 2,232,877,1611,1864,1493,860,358,105,20,2,376,1587,3262,4256

%N Triangle of coefficients of polynomials u(n,x) jointly generated with A207632; see the Formula section.

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

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

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

%e First five rows:

%e 1

%e 2

%e 4...2

%e 7...6...2

%e 12...15...8...2

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

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

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

%t Table[Factor[u[n, x]], {n, 1, z}]

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

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

%t TableForm[cu]

%t Flatten[%] (* A207631 *)

%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[%] (* A207632 *)

%Y Cf. A207632.

%K nonn,tabf

%O 1,2

%A _Clark Kimberling_, Feb 23 2012