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.

A385577 Array read by ascending antidiagonals: A(n,m) = n*Pochhammer(n+1,m+1)/(m+2).

Original entry on oeis.org

0, 1, 0, 3, 2, 0, 6, 8, 6, 0, 10, 20, 30, 24, 0, 15, 40, 90, 144, 120, 0, 21, 70, 210, 504, 840, 720, 0, 28, 112, 420, 1344, 3360, 5760, 5040, 0, 36, 168, 756, 3024, 10080, 25920, 45360, 40320, 0, 45, 240, 1260, 6048, 25200, 86400, 226800, 403200, 362880, 0
Offset: 0

Views

Author

Stefano Spezia, Jul 03 2025

Keywords

Examples

			Array begins as:
   0,  0,   0,    0,     0,     0,      0, ...
   1,  2,   6,   24,   120,   720,   5040, ...
   3,  8,  30,  144,   840,  5760,  45360, ...
   6, 20,  90,  504,  3360, 25920, 226800, ...
  10, 40, 210, 1344, 10080, 86400, 831600, ...
  ...
		

References

  • James J. Tattersall, Elementary Number Theory in Nine Chapters, Cambridge University Press, 1999, page 20.

Crossrefs

Cf. A000217 (m=0), A033487 (m=2), A158874 (m=3).
Cf. A000004 (n=0).

Programs

  • Mathematica
    A[n_,m_]:=n*Pochhammer[n+1,m+1]/(m+2); Table[A[n-m,m],{n,0,9},{m,0,n}]//Flatten

Formula

Sum_{m=0..n} A(n-m,m) = A006231(n+1).
A(n,1) = A007290(n+2).
A(1,n) = A000142(n+1).
A(2,n) = A001048(n+2).
A(3,n) = abs(A238474(n+1)).
A(n,n) = n!*A002740(n+2)