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.

A124326 T(n,m) = A007318(n,m) - A077028(n,m).

Original entry on oeis.org

1, 3, 3, 6, 10, 6, 10, 22, 22, 10, 15, 40, 53, 40, 15, 21, 65, 105, 105, 65, 21, 28, 98, 185, 226, 185, 98, 28, 36, 140, 301, 431, 431, 301, 140, 36, 45, 192, 462, 756, 887, 756, 462, 192, 45, 55, 255, 678, 1246, 1673, 1673, 1246, 678, 255, 55, 66, 330, 960, 1956, 2954
Offset: 1

Views

Author

Roger L. Bagula, Jun 26 2007

Keywords

Comments

First term of n-th row is n*(n+1)/2.
Row sum are A002663 (without initial zeros).
Appears to be the triangle resulting from adding the row number (first row numbered 0) of Pascal's triangle (A007318) to each entry in that row, subtracting the corresponding entries in the triangle formed by taking the finite diagonals in the multiplication table in order of increasing length (A003991), and removing the outer two layers, which consist entirely of 0's.
Each value of the sequence T(x,y) is equal to the sum of all values in A014430 that are in the rectangle defined by the tip (0,0) and the position (x,y). - Jon Perry, Sep 11 2013

Examples

			Table begins
   1;
   3,   3;
   6,  10,   6;
  10,  22,  22,  10;
  15,  40,  53,  40,  15;
  21,  65, 105, 105,  65,  21;
  28,  98, 185, 226, 185,  98,  28;
  36, 140, 301, 431, 431, 301, 140,  36;
  45, 192, 462, 756, 887, 756, 462, 192,  45;
  ...
If the zeros are included, the table begins
   0;
   0, 0;
   0, 0, 0;
   0, 0, 0, 0;
   0, 0, 1, 0, 0;
   0, 0, 3, 3, 0, 0;
   0, 0, 6, 10, 6, 0, 0;
   0, 0, 10, 22, 22, 10, 0, 0;
   ... - from _Michael De Vlieger_, May 27 2024
		

Crossrefs

Programs

  • Mathematica
    a = Table[Flatten[Table[If[Binomial[m, n] - (1 +n (m - n)) == 0, {}, Binomial[m, n] - (1 + n (m - n))], {n, 0, m}]], {m, 0, 14}]

Formula

T(n,m) = A007318(n,m) - A077028(n,m) (skipping zeros).