cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A207632 Triangle of coefficients of polynomials v(n,x) jointly generated with A207631; see Formula section.

Original entry on oeis.org

1, 2, 2, 3, 4, 2, 5, 9, 6, 2, 8, 18, 17, 8, 2, 13, 35, 41, 27, 10, 2, 21, 66, 93, 76, 39, 12, 2, 34, 122, 200, 196, 125, 53, 14, 2, 55, 222, 415, 472, 360, 190, 69, 16, 2, 89, 399, 837, 1083, 957, 603, 273, 87, 18, 2, 144, 710, 1651, 2392, 2400, 1750, 945, 376
Offset: 1

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Author

Clark Kimberling, Feb 23 2012

Keywords

Comments

Column 1: Fibonacci numbers, A000045.

Examples

			First five rows:
1
2...2
3...4....2
5...9....6....2
8...18...17...8...2
		

Crossrefs

Cf. A207631.

Programs

  • 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 + 1)*u[n - 1, x] + 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[%]  (* A207631 *)
    Table[Expand[v[n, x]], {n, 1, z}]
    cv = Table[CoefficientList[v[n, x], x], {n, 1, z}];
    TableForm[cv]
    Flatten[%]  (* A207632 *)

Formula

u(n,x)=u(n-1,x)+v(n-1,x),
v(n,x)=(x+1)*u(n-1,x)+x*v(n-1,x)+1,
where u(1,x)=1, v(1,x)=1.