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.

A059217 The array in A059216 read by antidiagonals in 'up' direction.

Original entry on oeis.org

1, 1, 2, 5, 3, 1, 1, 6, 10, 14, 45, 37, 26, 15, 1, 1, 46, 84, 121, 150, 169, 740, 686, 592, 471, 321, 170, 1, 1, 741, 1428, 2111, 2704, 3183, 3532, 3721, 21142, 20347, 18826, 16685, 13953, 10777, 7255, 3722, 1, 1, 21143, 41491, 61798, 80598
Offset: 1

Views

Author

Floor van Lamoen, Jan 18 2001

Keywords

Examples

			The array begins
   1  2  1 14  1 ...
   1  3 10 15 ...
   5  6 26 ...
   1 37 ...
  45 ...
		

Crossrefs

Programs

  • Maple
    See A059216 for Maple code.
  • Mathematica
    max = 9; t[0, 0] = 1; t[0, ?EvenQ] = 1; t[?OddQ, 0] = 1; t[n_, k_] /; OddQ[n + k](*up*):= t[n, k] = t[n+1, k-1] + Sum[t[n, j], {j, 0, k-1}]; t[n_, k_] /; EvenQ[n + k](*down*):= t[n, k] = t[n-1, k+1] + Sum[t[j, k], {j, 0, n-1}]; Table[t[n-k, k], {n, 0, max}, {k, 0, n}] // Flatten (* Jean-François Alcover, Sep 16 2013 *)