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A209581 Triangle of coefficients of polynomials u(n,x) jointly generated with A209582; see the Formula section. 3

%I #6 Mar 30 2012 18:58:15

%S 1,1,1,2,4,1,2,8,11,1,3,12,25,26,1,3,19,51,71,57,1,4,24,88,180,190,

%T 120,1,4,34,136,348,566,486,247,1,5,40,206,628,1238,1648,1199,502,1,5,

%U 53,282,1034,2526,4070,4545,2873,1013,1,6,60,395,1600,4556,9208

%N Triangle of coefficients of polynomials u(n,x) jointly generated with A209582; see the Formula section.

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

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

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

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

%e First five rows:

%e 1

%e 1...1

%e 2...4....1

%e 2...8....11...1

%e 3...12...25...26...1

%e First three polynomials v(n,x): 1, 1 + x, 2 + 4x + x^2.

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

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

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

%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[%] (* A209581 *)

%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[%] (* A209582 *)

%Y Cf. A209582, A208510.

%K nonn,tabl

%O 1,4

%A _Clark Kimberling_, Mar 11 2012

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Last modified July 25 02:31 EDT 2024. Contains 374585 sequences. (Running on oeis4.)