A210871 Triangle of coefficients of polynomials v(n,x) jointly generated with A210870; see the Formula section.
1, 1, 2, 1, 1, 3, 1, 3, 2, 5, 1, 2, 7, 3, 8, 1, 4, 5, 15, 5, 13, 1, 3, 12, 10, 30, 8, 21, 1, 5, 9, 31, 20, 58, 13, 34, 1, 4, 18, 22, 73, 38, 109, 21, 55, 1, 6, 14, 54, 51, 162, 71, 201, 34, 89, 1, 5, 25, 40, 145, 111, 344, 130, 365, 55, 144, 1, 7, 20, 85, 105, 361, 233
Offset: 1
Examples
First six rows: 1 1...2 1...1...3 1...3...2....5 1...2...7....3....8 1...4...5....15...5...13 First three polynomials v(n,x): 1, 1 + 2x, 1 + x + 3x^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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