A210225 Triangle of coefficients of polynomials u(n,x) jointly generated with A210226; see the Formula section.
1, 2, 1, 3, 5, 1, 4, 12, 10, 1, 5, 22, 36, 17, 1, 6, 35, 88, 87, 26, 1, 7, 51, 175, 277, 181, 37, 1, 8, 70, 306, 680, 734, 338, 50, 1, 9, 92, 490, 1416, 2196, 1710, 582, 65, 1, 10, 117, 736, 2632, 5402, 6156, 3606, 941, 82, 1, 11, 145, 1053, 4502, 11592
Offset: 1
Examples
First five rows: 1 2...1 3...5....1 4...12...10...1 5...22...36...17...1 First three polynomials u(n,x): 1, 2 + x, 3 + 5x + x^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] + 1; v[n_, x_] := 2 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[%] (* A210225 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A210226 *)
Formula
u(n,x)=x*u(n-1,x)+v(n-1,x)+1,
v(n,x)=2x*u(n-1,x)+(x+1)*v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.
Comments