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Triangle of coefficients of polynomials v(n,x) jointly generated with A208763; see the Formula section.
3

%I #11 Sep 08 2013 19:59:31

%S 1,0,3,0,2,7,0,2,6,19,0,2,6,26,47,0,2,6,34,78,123,0,2,6,42,110,258,

%T 311,0,2,6,50,142,426,758,803,0,2,6,58,174,626,1366,2282,2047,0,2,6,

%U 66,206,858,2134,4594,6558,5259,0,2,6,74,238,1122,3062,7866,14334

%N Triangle of coefficients of polynomials v(n,x) jointly generated with A208763; see the Formula section.

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

%C As triangle T(n,k) with 0<=k<=n, it is (0, 2/3, 1/3, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (3, -2/3, -4/3, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - _Philippe Deléham_, Mar 02 2012

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

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

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

%F As triangle T(n,k), 0 <=k<=n :

%F G.f.: (1-x+2y*x)/(1-(1+y)*x -(4*y^2-y)*x^2). - _Philippe Deléham_, Mar 02 2012

%F As triangle T(n,k), 0<=k<=n : T(n,k) = T(n-1,k) + T(n-1,k-1) + 4*T(n-2,k-2) - T(n-2,k-1) with T(0,0) = 1, T(1,0) = 0, T(1,1) = 3 and T(n,k) = 0 if k<0 or if k>n. - _Philippe Deléham_, Mar 02 2012

%e First five rows:

%e 1

%e 0...3

%e 0...2...7

%e 0...2...6...19

%e 0...2...6...26...47

%e First five polynomials v(n,x):

%e 1

%e 3x

%e 2x + 7x^2

%e 2x + 6x^2 + 19x^3

%e 2x + 6x^2 + 26x^3 + 47x^4

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

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

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

%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[%] (* A208763 *)

%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[%] (* A208764 *)

%Y Cf. A208763, A208510.

%K nonn,tabl

%O 1,3

%A _Clark Kimberling_, Mar 02 2012