A280880 as a triangular array
| | | | | | | | | | | 1 |
| | | | | | | | | | | 0 | | 1 |
| | | | | | | | | | 0 | | 1 | | 1 |
| | | | | | | | | 0 | | 1 | | 3 | | 1 |
| | | | | | | | 0 | | 1 | | 4 | | 6 | | 1 |
| | | | | | | 0 | | 1 | | 15 | | 10 | | 10 | | 1 |
| | | | | | 0 | | 1 | | 6 | | 75 | | 20 | | 15 | | 1 |
| | | | | 0 | | 1 | | 63 | | 21 | | 245 | | 35 | | 21 | | 1 |
| | | | 0 | | 1 | | 64 | | 476 | | 56 | | 630 | | 56 | | 28 | | 1 |
| | | 0 | | 1 | | 171 | | 540 | | 2100 | | 126 | | 1386 | | 84 | | 36 | | 1 |
| | 0 | | 1 | | 130 | | 4185 | | 2640 | | 6930 | | 252 | | 2730 | | 120 | | 45 | | 1 |
|
A280880 as a square array
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
| | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | 1 | 3 | 4 | 15 | 6 | 63 | 64 | 171 | 130
| | 1 | 6 | 10 | 75 | 21 | 476 | 540 | 4185
| | 1 | 10 | 20 | 245 | 56 | 2100 | 2640
| | 1 | 15 | 35 | 630 | 126 | 6930
| | 1 | 21 | 56 | 1386 | 252
| | 1 | 28 | 84 | 2730
| | 1 | 36 | 120
| | 1 | 45
| | 1
|
A280880 as an upper right triangle
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
| | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | | 1 | 3 | 4 | 15 | 6 | 63 | 64 | 171 | 130
| | | | 1 | 6 | 10 | 75 | 21 | 476 | 540 | 4185
| | | | | 1 | 10 | 20 | 245 | 56 | 2100 | 2640
| | | | | | 1 | 15 | 35 | 630 | 126 | 6930
| | | | | | | 1 | 21 | 56 | 1386 | 252
| | | | | | | | 1 | 28 | 84 | 2730
| | | | | | | | | 1 | 36 | 120
| | | | | | | | | | 1 | 45
| | | | | | | | | | | 1
|
|
