A209569 Triangle of coefficients of polynomials u(n,x) jointly generated with A209570; see the Formula section.
1, 1, 1, 2, 3, 1, 3, 6, 5, 1, 4, 11, 14, 7, 1, 5, 18, 31, 26, 9, 1, 6, 27, 60, 71, 42, 11, 1, 7, 38, 105, 162, 139, 62, 13, 1, 8, 51, 170, 327, 372, 243, 86, 15, 1, 9, 66, 259, 602, 861, 754, 391, 114, 17, 1, 10, 83, 376, 1031, 1790, 1987, 1388, 591, 146, 19, 1
Offset: 1
Examples
First five rows: 1 1...1 2...3....1 3...6....5....1 4...11...14...7...1 First three polynomials v(n,x): 1, 1 + x, 2 + 3x + x^2.
Programs
-
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_] := 2 x*u[n - 1, x] + 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[%] (* A209569 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A209570 *)
Formula
u(n,x)=x*u(n-1,x)+v(n-1,x),
v(n,x)=2x*u(n-1,x)+v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.
Comments