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

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

1,3

Links

G. C. Greubel, Table of n, a(n) for the first 50 rows, flattened

Example

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

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 *)

Crossrefs

Cf. A000667, A059216, A059219, A059220, A059234.

Sequence in context: A326953 A234255 A062706 * A021802 A304174 A011192

Adjacent sequences: A059214 A059215 A059216 * A059218 A059219 A059220

Keyword

easy,nonn,tabl,nice

Author

Floor van Lamoen, Jan 18 2001

Status

approved