A207619 Triangle of coefficients of polynomials v(n,x) jointly generated with A207618; see the Formula section.
1, 1, 3, 1, 4, 6, 1, 5, 11, 12, 1, 6, 17, 28, 24, 1, 7, 24, 51, 68, 48, 1, 8, 32, 82, 142, 160, 96, 1, 9, 41, 122, 255, 376, 368, 192, 1, 10, 51, 172, 417, 744, 960, 832, 384, 1, 11, 62, 233, 639, 1323, 2072, 2384, 1856, 768, 1, 12, 74, 306, 933, 2184, 3974
Offset: 1
Examples
First five rows: 1 1...3 1...4...6 1...5...11...12 1...6...17...28...24
Crossrefs
Cf. A207618.
Programs
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Mathematica
u[1, x_] := 1; v[1, x_] := 1; z = 16; u[n_, x_] := u[n - 1, x] + v[n - 1, x] v[n_, x_] := x*u[n - 1, x] + 2 x*v[n - 1, x] + 1 Table[Factor[u[n, x]], {n, 1, z}] Table[Factor[v[n, x]], {n, 1, z}] cu = Table[CoefficientList[u[n, x], x], {n, 1, z}]; TableForm[cu] Flatten[%] (* A207618 *) Table[Expand[v[n, x]], {n, 1, z}] cv = Table[CoefficientList[v[n, x], x], {n, 1, z}]; TableForm[cv] Flatten[%] (* A207619 *)
Formula
u(n,x)=u(n-1,x)+v(n-1,x), v(n,x)=xu(n-1,x)+2x*v(n-1,x)+1, where u(1,x)=1, v(1,x)=1.
Comments