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.

A103252 Array A000292(n)*A000217(k), read by antidiagonals.

Original entry on oeis.org

1, 4, 3, 10, 12, 6, 20, 30, 24, 10, 35, 60, 60, 40, 15, 56, 105, 120, 100, 60, 21, 84, 168, 210, 200, 150, 84, 28, 120, 252, 336, 350, 300, 210, 112, 36, 165, 360, 504, 560, 525, 420, 280, 144, 45, 220, 495, 720, 840, 840, 735, 560, 360, 180, 55
Offset: 1

Views

Author

Gary W. Adamson, Mar 20 2005

Keywords

Examples

			Array begins
   1,   3,   6,  10,  15,  21,  28,   36,   45,   55, ...
   4,  12,  24,  40,  60,  84, 112,  144,  180,  220, ...
  10,  30,  60, 100, 150, 210, 280,  360,  450,  550, ...
  20,  60, 120, 200, 300, 420, 560,  720,  900, 1100, ...
  35, 105, 210, 350, 525, 735, 980, 1260, 1575, 1925, ...
  ...
		

Crossrefs

Cf. A000579 (antidiagonal sums).
Main diagonal gives A004302.

Programs

  • Mathematica
    A[n_,k_]:=Binomial[n+2,3]Binomial[k+1,2]; Table[A[n-k+1,k],{n,10},{k,n}]//Flatten (* Stefano Spezia, May 21 2023 *)

Formula

G.f.: x*y/((1 - x)^4*(1 - y)^3). - Stefano Spezia, May 21 2023

Extensions

More terms from Stefano Spezia, May 21 2023