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.

A140880 Triangle read by rows, T(n,k) = Gamma(n+3)/(Gamma(k+1)*Gamma(n-k+1)) for n>=0 and 0<=k<=n.

Original entry on oeis.org

2, 6, 6, 12, 24, 12, 20, 60, 60, 20, 30, 120, 180, 120, 30, 42, 210, 420, 420, 210, 42, 56, 336, 840, 1120, 840, 336, 56, 72, 504, 1512, 2520, 2520, 1512, 504, 72, 90, 720, 2520, 5040, 6300, 5040, 2520, 720, 90
Offset: 0

Views

Author

Roger L. Bagula and Gary W. Adamson, Jul 22 2008

Keywords

Examples

			Triangle starts:
[0] 2
[1] 6,    6
[2] 12,  24,   12
[3] 20,  60,   60,   20
[4] 30, 120,  180,  120,   30
[5] 42, 210,  420,  420,  210,   42
[6] 56, 336,  840, 1120,  840,  336,   56
[7] 72, 504, 1512, 2520, 2520, 1512,  504,  72
[8] 90, 720, 2520, 5040, 6300, 5040, 2520, 720, 90
		

Crossrefs

T(n,0) = T(n,n) = A002378(n+1). T(n,k) = 2*A094305(n,k).
Row sums are A001815(n+2).
Cf. A007318.

Programs

  • Maple
    T := (n,k) -> GAMMA(n+3)/(GAMMA(k+1)*GAMMA(n-k+1)):
    seq(seq(T(n,k), k=0..n), n=0..8); # Peter Luschny, Oct 29 2017
  • Mathematica
    Flatten[Table[Gamma[n+3]/(Gamma[k+1]Gamma[n-k+1]),{n,0,8},{k,0,n}]]

Extensions

Edited and new name from Peter Luschny, Oct 29 2017