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.

A142706 Coefficients of the derivatives of the Eulerian polynomials (with indexing as in A173018).

Original entry on oeis.org

1, 4, 2, 11, 22, 3, 26, 132, 78, 4, 57, 604, 906, 228, 5, 120, 2382, 7248, 4764, 600, 6, 247, 8586, 46857, 62476, 21465, 1482, 7, 502, 29216, 264702, 624760, 441170, 87648, 3514, 8, 1013, 95680, 1365576, 5241416, 6551770, 2731152, 334880, 8104, 9
Offset: 1

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Author

Roger L. Bagula and Gary W. Adamson, Sep 24 2008

Keywords

Examples

			Triangle T(n, k) starts:
{   1};
{   4,     2};
{  11,    22,       3};
{  26,   132,      78,       4};
{  57,   604,     906,     228,       5};
{ 120,  2382,    7248,    4764,     600,       6};
{ 247,  8586,   46857,   62476,   21465,    1482,      7};
{ 502, 29216,  264702,  624760,  441170,   87648,   3514,   8};
{1013, 95680, 1365576, 5241416, 6551770, 2731152, 334880, 8104, 9}.
		

Crossrefs

Cf. A173018, A001286 (row sums).

Programs

  • Maple
    T := (n, k) -> k * combinat:-eulerian1(n+1, k):
    for n from 1 to 9 do seq(T(n, k), k = 1..n) od; # Peter Luschny, Feb 07 2023
  • Mathematica
    T[n_, k_] := Sum[(-1)^j Binomial[n + 1, j](k + 1 - j)^n, {j, 0, k + 1}];
    Table[D[Sum[T[n, k]*x^k, {k, 0, n - 1}], x], {n, 1, 10}];
    Table[CoefficientList[D[Sum[T[n, k]*x^k, {k, 0, n - 1}], x], x], {n, 1, 10}];
    Flatten[%]
    (* Alternative: *) Needs["Combinatorica`"]
    Flatten[Table[k*Eulerian[n+1, k], {n, 1, 9}, {k, 1, n}]] (* Peter Luschny, Feb 07 2023 *)

Formula

Let E(n, x) = Sum_{j=0..k} A173018(n, k)*x^k and E'(n, x) = (d/dx) E(x, n). Then T(n, k) = [x^(k-1)] E'(n+1, x).

Extensions

Edited by Peter Luschny, Feb 07 2023