A210556 Triangle of coefficients of polynomials v(n,x) jointly generated with A210555; see the Formula section.
1, 2, 2, 3, 4, 4, 4, 6, 10, 8, 5, 8, 18, 22, 16, 6, 10, 28, 42, 50, 32, 7, 12, 40, 68, 106, 110, 64, 8, 14, 54, 100, 188, 250, 242, 128, 9, 16, 70, 138, 300, 468, 594, 526, 256, 10, 18, 88, 182, 446, 780, 1188, 1378, 1138, 512, 11, 20, 108, 232, 630, 1202
Offset: 1
Examples
First five rows: 1 2...2 3...4...4 4...6...10...8 5...8...18...22...16 First three polynomials v(n,x): 1, 2 + 2x , 3 + 4x + 4x^2.
Programs
-
Mathematica
u[1, x_] := 1; v[1, x_] := 1; z = 16; u[n_, x_] := x*u[n - 1, x] + x*v[n - 1, x] + 1; 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[%] (* A210555 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A210556 *)
Formula
u(n,x)=x*u(n-1,x)+x*v(n-1,x)+1,
v(n,x)=2x*u(n-1,x)+v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.
Comments