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Triangle of coefficients of polynomials v(n,x) jointly generated with A208749; see the Formula section.
3

%I #14 Jan 24 2020 03:30:22

%S 1,2,1,3,4,2,4,11,10,2,5,24,32,16,4,6,45,84,72,32,4,7,76,194,240,156,

%T 48,8,8,119,406,666,592,300,88,8,9,176,784,1632,1896,1344,576,128,16,

%U 10,249,1416,3648,5344,4904,2848,1024,224,16,11,340,2418,7584

%N Triangle of coefficients of polynomials v(n,x) jointly generated with A208749; see the Formula section.

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

%C Subtriangle of the triangle T(n,k) given by (1, 1, -1, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 1, 1, -2, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - _Philippe Deléham_, Mar 16 2012

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

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

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

%F As DELTA-triangle with 0 <= k <= n: g.f.: (1-x+x^2-y*x^2-2*t^2*x^2)/(1-2*x+x^2-2*y*x^2-2*y^2*x^2). - _Philippe Deléham_, Mar 16 2012

%F As DELTA-triangle: T(n,k) = 2*T(n-1,k) - T(n-2,k) + 2*T(n-2,k-1) + 2*T(n-2,k-2), T(0,0) = T(1,0) = T(2,1) = 1, T(2,0) = 2, T(1,1) = T(2,2) = 0 and T(n,k) = 0 if k < 0 or if k > n. - _Philippe Deléham_, Mar 16 2012

%e First five rows:

%e 1;

%e 2, 1;

%e 3, 4, 2;

%e 4, 11, 10, 2;

%e 5, 24, 32, 16, 4;

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

%e 1

%e 2 + x

%e 3 + 4x + 2x^2

%e 4 + 11x + 10x^2 + 2x^3

%e 5 + 24x + 32x^2 + 16x^3 + 4x^4

%e From _Philippe Deléham_, Mar 16 2012: (Start)

%e (1, 1, -1, 1, 0, 0, ...) DELTA (0, 1, 1, -2, 0, 0, ...) begins:

%e 1;

%e 1, 0;

%e 2, 1, 0;

%e 3, 4, 2, 0;

%e 4, 11, 10, 2, 0;

%e 5, 24, 32, 16, 4, 0;

%e 6, 45, 84, 72, 32, 4, 0; (End)

%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_] := (x + 1)*u[n - 1, 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[%] (* A208749 *)

%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[%] (* A208750 *)

%Y Cf. A208749, A208510.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Mar 02 2012