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.

A193924 Mirror of the triangle A193923.

Original entry on oeis.org

1, 1, 1, 3, 2, 1, 8, 5, 3, 1, 21, 13, 8, 4, 1, 55, 34, 21, 12, 5, 1, 144, 89, 55, 33, 17, 6, 1, 377, 233, 144, 88, 50, 23, 7, 1, 987, 610, 377, 232, 138, 73, 30, 8, 1, 2584, 1597, 987, 609, 370, 211, 103, 38, 9, 1, 6765, 4181, 2584, 1596, 979, 581, 314, 141, 47
Offset: 0

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Author

Clark Kimberling, Aug 09 2011

Keywords

Comments

A193924 is obtained by reversing the rows of the triangle A193923.

Examples

			First six rows:
1
1....1
3....2....1
8....5....3....1
21...13...8....4....1
55...34...21...12...5...1
		

Crossrefs

Cf. A193923.

Programs

  • Mathematica
    p[n_, x_] := (x + 1)^n;
    q[n_, x_] := Sum[Fibonacci[k + 1]*x^(n - k), {k, 0, n}];
    t[n_, k_] := Coefficient[p[n, x], x^k]; t[n_, 0] := p[n, x] /. x -> 0;
    w[n_, x_] := Sum[t[n, k]*q[n + 1 - k, x], {k, 0, n}]; w[-1, x_] := 1
    g[n_] := CoefficientList[w[n, x], {x}]
    TableForm[Table[Reverse[g[n]], {n, -1, z}]]
    Flatten[Table[Reverse[g[n]], {n, -1, z}]]  (* A193923 *)
    TableForm[Table[g[n], {n, -1, z}]]
    Flatten[Table[g[n], {n, -1, z}]]  (* A193924 *)

Formula

Write w(n,k) for the triangle at A193923. The triangle at A193924 is then given by w(n,n-k).