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.

A344640 Antidiagonal sums of A344639.

Original entry on oeis.org

1, 2, 5, 16, 63, 297, 1649, 10641, 78823, 662315, 6241889, 65294039, 751035233, 9420926879, 127958645921, 1870319380463, 29263787708393, 487891616911031, 8632986776222945, 161555987833199807, 3187606376603319017, 66128414623822131863, 1438861202348688524897, 32763278185929878499887
Offset: 0

Views

Author

Stefano Spezia, May 25 2021

Keywords

Crossrefs

Programs

  • Mathematica
    Table[Sum[Sum[Abs[StirlingS1[n-k,m]](m+1)^k,{m,0,n-k}],{k,0,n}],{n,0,23}]

Formula

a(n) = Sum_{k=0..n} Sum_{m=0..n-k} abs(S1(n-k, m))*(m + 1)^k, where S1 indicates the signed Stirling numbers of first kind.
Conjecture: a(n) ~ n!. - Vaclav Kotesovec, May 26 2021