A210870 Triangle of coefficients of polynomials u(n,x) jointly generated with A210871; see the Formula section.
1, 1, 1, 1, 2, 2, 1, 3, 3, 3, 1, 4, 6, 5, 5, 1, 5, 8, 12, 8, 8, 1, 6, 12, 17, 23, 13, 13, 1, 7, 15, 29, 33, 43, 21, 21, 1, 8, 20, 38, 64, 63, 79, 34, 34, 1, 9, 24, 56, 86, 136, 117, 143, 55, 55, 1, 10, 30, 70, 140, 187, 279, 214, 256, 89, 89, 1, 11, 35, 95, 180, 332
Offset: 1
Examples
First six rows: 1 1...1 1...2...2 1...3...3...3 1...4...6...5....5 1...5...8...12...8...8 First three polynomials u(n,x): 1, 1 + x, 1 + 2x + 2x^2.
Programs
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Mathematica
u[1, x_] := 1; v[1, x_] := 1; z = 14; u[n_, x_] := u[n - 1, x] + x*v[n - 1, x]; v[n_, x_] := (x + 1)*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[%] (* A210870 *) cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A210871 *) Table[u[n, x] /. x -> 1, {n, 1, z}] (* A000975 *) Table[v[n, x] /. x -> 1, {n, 1, z}] (* A001045 *) Table[u[n, x] /. x -> -1, {n, 1, z}] (* A113954 *) Table[v[n, x] /. x -> -1, {n, 1, z}] (* A077925 *)
Formula
u(n,x)=u(n-1,x)+x*v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+(x-1)*v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.
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