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A208335 Triangle of coefficients of polynomials v(n,x) jointly generated with A208834; see the Formula section. 4

%I #13 Jan 22 2020 20:13:06

%S 1,2,1,3,3,1,4,7,5,1,5,14,15,6,1,6,25,36,23,8,1,7,41,76,69,36,9,1,8,

%T 63,147,176,123,48,11,1,9,92,266,400,355,192,66,12,1,10,129,456,834,

%U 910,635,292,82,14,1,11,175,747,1626,2131,1833,1065,410,105,15,1

%N Triangle of coefficients of polynomials v(n,x) jointly generated with A208834; see the Formula section.

%C row sums, u(n,1): A000129

%C row sums, v(n,1): A001333

%C alternating row sums, u(n,-1): 1,0,-1,-2,-3,-4,-5,-6,...

%C alternating row sums, v(n,-1): 1,1,1,1,1,1,1,1,1,1,1,...

%C Subtriangle of the triangle T(n,k) given by (1, 1, -1, 1, 0, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938. - _Philippe Deléham_, Mar 26 2012

%F u(n,x) = u(n-1,x) + x*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 From _Philippe Deléham_, Mar 26 2012: (Start)

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

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

%F T(n,k) = 2*T(n-1,k) - T(n-2,k) + T(n-2,k-1) + 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. (End)

%e First five rows:

%e 1;

%e 2, 1;

%e 3, 3, 1;

%e 4, 7, 5, 1;

%e 5, 14, 15, 6, 1;

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

%e 1

%e 2 + x

%e 3 + 3x + x^2

%e 4 + 7x + 5x^2 + x^3

%e 5 + 14x + 15x^2 + 6x^3 + x^4

%e From _Philippe Deléham_, Mar 26 2012: (Start)

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

%e 1;

%e 1, 0;

%e 2, 1, 0;

%e 3, 3, 1, 0;

%e 4, 7, 5, 1, 0;

%e 5, 14, 15, 6, 1, 0; (End)

%t u[1, x_] := 1; v[1, x_] := 1; z = 13;

%t u[n_, x_] := u[n - 1, x] + 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[%] (* A208334 *)

%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[%] (* A208335 *)

%t Table[u[n, x] /. x -> 1, {n, 1, z}] (* u row sums *)

%t Table[v[n, x] /. x -> 1, {n, 1, z}] (* v row sums *)

%t Table[u[n, x] /. x -> -1, {n, 1, z}](* u alt. row sums *)

%t Table[v[n, x] /. x -> -1, {n, 1, z}](* v alt. row sums *)

%Y Cf. A208334.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Feb 26 2012

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Last modified April 24 14:54 EDT 2024. Contains 371960 sequences. (Running on oeis4.)