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A208766 Triangle of coefficients of polynomials v(n,x) jointly generated with A208765; see the Formula section. 3

%I #18 Jan 24 2020 03:27:43

%S 1,1,3,1,6,7,1,9,21,19,1,12,42,76,47,1,15,70,190,235,123,1,18,105,380,

%T 705,738,311,1,21,147,665,1645,2583,2177,803,1,24,196,1064,3290,6888,

%U 8708,6424,2047,1,27,252,1596,5922,15498,26124,28908,18423

%N Triangle of coefficients of polynomials v(n,x) jointly generated with A208765; see the Formula section.

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

%C Subtriangle of the triangle given by (1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 3, -2/3, -4/3, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - _Philippe Deléham_, Mar 20 2012

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

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

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

%F From _Philippe Deléham_, Mar 20 2012: (Start)

%F As DELTA-triangle with 0 <= k <= n:

%F G.f.: (1-x-y*x+3*y*x^2-4*y^2*x^2)/(1-2*x-y*x+x^2+y*x^2-4*y^2*x^2).

%F T(n,k) = 2*T(n-1,k) + T(n-1,k-1) - T(n-2,k) - T(n-2,k-1) + 4*T(n-2,k-2), T(0,0) = T(1,0) = T(2,0) = 1, T(1,1) = T(2,2) = 0, T(2,1) = 3 and T(n,k) = 0 if k < 0 or if k > n. (End)

%e First five rows:

%e 1;

%e 1, 3;

%e 1, 6, 7;

%e 1, 9, 21, 19;

%e 1, 12, 42, 76, 47;

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

%e 1

%e 1 + 3x

%e 1 + 6x + 7x^2

%e 1 + 9x + 21x^2 + 19x^3

%e 1 + 12x + 42x^2 + 76x^3 + 47x^4

%e From _Philippe Deléham_, Mar 20 2012: (Start)

%e (1, 0, 0, 1, 0, 0, ...) DELTA (0, 3, -2/3, -4/3, 0, 0, ...) begins:

%e 1;

%e 1, 0;

%e 1, 3, 0;

%e 1, 6, 7, 0;

%e 1, 9, 21, 19, 0;

%e 1, 12, 42, 76, 47, 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_] := 2 x*u[n - 1, x] + (x + 1) 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[%] (* A208765 *)

%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[%] (* A208766 *)

%Y Cf. A208765, A208510.

%K nonn,tabl

%O 1,3

%A _Clark Kimberling_, Mar 02 2012

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Last modified April 19 04:26 EDT 2024. Contains 371782 sequences. (Running on oeis4.)