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Triangle of coefficients of polynomials v(n,x) jointly generated with A208612; see the Formula section.
3

%I #6 Mar 30 2012 18:58:13

%S 1,3,2,5,7,3,7,17,16,5,9,34,51,33,8,11,60,127,129,65,13,13,97,272,386,

%T 302,124,21,15,147,525,975,1052,666,231,34,17,212,938,2186,3049,2646,

%U 1409,423,55,19,294,1578,4482,7757,8650,6285,2887,764,89,21

%N Triangle of coefficients of polynomials v(n,x) jointly generated with A208612; see the Formula section.

%C Alternating row sums: 1,1,1,1,1,1,1,1,1,1,1,...

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

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

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

%e First five rows:

%e 1

%e 3...2

%e 5...7....3

%e 7...17...16...3

%e 9...34...51...33...8

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

%e 1

%e 3 + 2x

%e 5 + 7x + 3x^2

%e 7 + 17x + 16x^2 + 3x^3

%e 9 + 34x + 51x^2 + 33x^3 + 8x^4

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

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

%t v[n_, x_] := (x + 1)*u[n - 1, x] + (x + 1)*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[%] (* A208612 *)

%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[%] (* A208613 *)

%Y Cf. A208612.

%K nonn,tabl

%O 1,2

%A _Clark Kimberling_, Mar 01 2012