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.

A111885 Row sums of triangle A112492.

Original entry on oeis.org

1, 2, 5, 20, 152, 2542, 100326, 10194844, 2809233510, 2212797607312, 5359196565766782, 39928779843430949176, 1018129474625651322506886, 85890171235256453902613870992, 26477529277143069417959927152215342
Offset: 0

Views

Author

Wolfdieter Lang, Sep 12 2005

Keywords

Crossrefs

Cf. A112492.

Programs

  • Magma
    T:= func< n,k | (-1)*Factorial(k+1)^(n-k)*(&+[(-1)^j*Binomial(k+1,j)/j^(n-k) : j in [1..k+1]]) >; // T = A112492
    A111885:= func< n | (&+[T(n,k): k in [0..n]]) >;
    [A111885(n): n in [0..40]]; // G. C. Greubel, Jul 24 2023
    
  • Mathematica
    T[n_, k_]:= T[n, k]= If[k==0 || k==n, 1, (k+1)^(n-k)*T[n-1, k-1] + k!*T[n-1, k]];
    a[n_]:= a[n]= Sum[T[n,k], {k,0,n}]; (* T = A112492 *)
    Table[a[n], {n,0,40}] (* G. C. Greubel, Jul 24 2023 *)
  • SageMath
    @CachedFunction
    def T(n,k): # T = A112492
        if (k==0 or k==n): return 1
        else: return (k+1)^(n-k)*T(n-1,k-1) + factorial(k)*T(n-1,k)
    def A111885(n): return sum(T(n,k) for k in range(n+1))
    [A111885(n) for n in range(31)] # G. C. Greubel, Jul 24 2023

Formula

a(n) = Sum_{j=0..n} A112492(n, j), n >= 0.