A209568 Triangle of coefficients of polynomials v(n,x) jointly generated with A209567; see the Formula section.
1, 2, 2, 3, 5, 3, 4, 10, 11, 4, 5, 17, 28, 21, 5, 6, 26, 58, 67, 36, 6, 7, 37, 105, 166, 142, 57, 7, 8, 50, 173, 350, 416, 274, 85, 8, 9, 65, 266, 659, 1011, 940, 491, 121, 9, 10, 82, 388, 1141, 2156, 2612, 1955, 829, 166, 10, 11, 101, 543, 1852, 4172, 6265
Offset: 1
Examples
First five rows: 1 2...2 3...5...3 4...10...11...4 5...17...28...21...5 First three polynomials v(n,x): 1, 2+2x, 3+5x+3x^2.
Programs
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Mathematica
u[1, x_] := 1; v[1, x_] := 1; z = 16; u[n_, x_] := x*u[n - 1, x] + v[n - 1, x]; v[n_, x_] := x*u[n - 1, x] + (x + 1)*v[n - 1, x] + 1; Table[Expand[u[n, x]], {n, 1, z/2}] Table[Expand[v[n, x]], {n, 1, z/2}] cu = Table[CoefficientList[u[n, x], x], {n, 1, z}]; TableForm[cu] Flatten[%] (* A209567 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A209568 *)
Formula
u(n,x)=x*u(n-1,x)+v(n-1,x),
v(n,x)=x*u(n-1,x)+(x+1)*v(n-1,x) +1,
where u(1,x)=1, v(1,x)=1.
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