A210805 Triangle of coefficients of polynomials u(n,x) jointly generated with A210806; see the Formula section.
1, 1, 1, 1, 1, 2, 1, 2, 3, 3, 1, 2, 6, 6, 5, 1, 3, 8, 14, 12, 8, 1, 3, 12, 22, 31, 23, 13, 1, 4, 15, 37, 56, 65, 43, 21, 1, 4, 20, 52, 102, 132, 132, 79, 34, 1, 5, 24, 76, 160, 260, 296, 261, 143, 55, 1, 5, 30, 100, 250, 446, 626, 639, 506, 256, 89, 1, 6, 35, 135, 360
Offset: 1
Examples
First five rows: 1 1...1 1...1...2 1...2...3...3 1...2...6...6...5 First three polynomials u(n,x): 1, 1 + x, 1 + x + 2x^2.
Programs
-
Mathematica
u[1, x_] := 1; v[1, x_] := 1; z = 16; u[n_, x_] := u[n - 1, x] + (x + j)*v[n - 1, x] + c; d[x_] := h + x; e[x_] := p + x; v[n_, x_] := d[x]*u[n - 1, x] + e[x]*v[n - 1, x] + f; j = 0; c = 0; h = 2; p = -1; f = -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[%] (* A210805 *) cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A210806 *)
Formula
u(n,x)=u(n-1,x)+x*v(n-1,x),
v(n,x)=(x+2)*u(n-1,x)+(x-1)*v(n-1,x)-1,
where u(1,x)=1, v(1,x)=1.
Comments