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.

A375466 Array read by ascending antidiagonals of triangles read by rows: the coefficients of the polynomials n! * m^(n-k) * x^k * A094587(n, k), for m >= 0.

Original entry on oeis.org

1, 1, 0, 1, 1, 1, 1, 2, 1, 0, 1, 3, 1, 2, 0, 1, 4, 1, 8, 2, 1, 1, 5, 1, 18, 4, 1, 0, 1, 6, 1, 32, 6, 1, 6, 0, 1, 7, 1, 50, 8, 1, 48, 6, 0, 1, 8, 1, 72, 10, 1, 162, 24, 3, 1, 1, 9, 1, 98, 12, 1, 384, 54, 6, 1, 0, 1, 10, 1, 128, 14, 1, 750, 96, 9, 1, 24, 0
Offset: 0

Views

Author

Peter Luschny, Aug 17 2024

Keywords

Examples

			Sequence of polynomials P(n, m) for n = 0, 1, 2, ...:
  [0]   1;
  [1]   1*m   +         x;
  [2]   2*m^2 +     2*m*x +         x^2;
  [3]   6*m^3 +   6*m^2*x +     3*m*x^2 +         x^3;
  [4]  24*m^4 +  24*m^3*x +  12*m^2*x^2 +     4*m*x^3 +        x^4;
  [5] 120*m^5 + 120*m^4*x +  60*m^3*x^2 +  20*m^2*x^3 +    5*m*x^4 +     x^5;
  [6] 720*m^6 + 720*m^5*x + 360*m^4*x^2 + 120*m^3*x^3 + 30*m^2*x^4 + 6*m*x^5 + x^6;
  ...
Array of the coefficients of the polynomials for m = 0, 1, 2, ...:
  [0] 1, 0, 1,  0,  0, 1,    0,   0,  0, 1,     0,    0,   0,  0, 1, ...  A023531
  [1] 1, 1, 1,  2,  2, 1,    6,   6,  3, 1,    24,   24,  12,  4, 1, ...  A094587
  [2] 1, 2, 1,  8,  4, 1,   48,  24,  6, 1,   384,  192,  48,  8, 1, ...
  [3] 1, 3, 1, 18,  6, 1,  162,  54,  9, 1,  1944,  648, 108, 12, 1, ...
  [4] 1, 4, 1, 32,  8, 1,  384,  96, 12, 1,  6144, 1536, 192, 16, 1, ...
  [5] 1, 5, 1, 50, 10, 1,  750, 150, 15, 1, 15000, 3000, 300, 20, 1, ...
  [6] 1, 6, 1, 72, 12, 1, 1296, 216, 18, 1, 31104, 5184, 432, 24, 1, ...
  ...
Seen as triangle:
  1;
  1, 0;
  1, 1, 1;
  1, 2, 1,  0;
  1, 3, 1,  2,  0;
  1, 4, 1,  8,  2, 1;
  1, 5, 1, 18,  4, 1,   0;
  1, 6, 1, 32,  6, 1,   6,  0;
  1, 7, 1, 50,  8, 1,  48,  6, 0;
  1, 8, 1, 72, 10, 1, 162, 24, 3, 1;
  1, 9, 1, 98, 12, 1, 384, 54, 6, 1,  0;
		

Crossrefs

Programs

  • Maple
    # Computes the polynomials depending on the parameter m.
    P := (n, m) -> ifelse(m = 0, x^n, n! * m^n * hypergeom([-n], [-n], x/m)):
    seq(print(simplify(P(n, m))), n = 0..5);
    # Computes the array of coefficients:
    P := (n, k, m) -> (n!/k!) * m^(n-k) * x^k:
    Arow := (m, len) -> local n, k;
    seq(seq(coeff(P(n, k, m), x, k), k = 0..n), n = 0..len):
    seq(lprint(Arow(n, 4)), n = 0..6);

Formula

T(n, m, k) = [x^k] n! * m^n * hypergeom([-n], [-n], x/m), for n > 0.