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.

A094422 Antidiagonal sums of array A094416.

Original entry on oeis.org

1, 5, 26, 174, 1531, 17275, 243092, 4165260, 85133685, 2039546785, 56447550542, 1783865468186, 63766726231791, 2558290237404919, 114418196763735112, 5670168958036693976, 309630356618418661737, 18536683645526372648445
Offset: 1

Views

Author

Ralf Stephan, May 02 2004

Keywords

Crossrefs

Cf. A094416.

Programs

  • Magma
    A094422:= func< n | (&+[(&+[Factorial(j)*(n-k+1)^j*StirlingSecond(k,j): j in [0..n]]): k in [1..n]]) >;
    [A094422(n): n in [1..25]]; // G. C. Greubel, Jan 11 2024
    
  • Mathematica
    Table[Sum[Sum[j!*(n - k + 1)^j*StirlingS2[k, j], {j, 0, n}], {k, 1, n}], {n, 1, 20}] (* Vaclav Kotesovec, Jul 23 2018 *)
  • SageMath
    def f(n,k,j): return factorial(j)*(n-k+1)^j*stirling_number2(k,j)
    def A094422(n): return sum(sum(f(n,k,j) for j in range(n+1)) for k in range(1,n+1))
    [A094422(n) for n in range(1,26)] # G. C. Greubel, Jan 11 2024

Formula

a(n) = Sum_{k=1..n} Bo(n-k+1, k), where Bo(r, n) = A094416(r, n).