A013580 formatted as a triangular array:
| | | | | | | | | | 1 | | | | | | | | | | |
| | | | | | | | | 1 | | 1 | | | | | | | | | |
| | | | | | | | 1 | | 3 | | 1 | | | | | | | | |
| | | | | | | 1 | | 4 | | 4 | | 1 | | | | | | | |
| | | | | | 1 | | 5 | | 9 | | 5 | | 1 | | | | | | |
| | | | | 1 | | 6 | | 14 | | 14 | | 6 | | 1 | | | | | |
| | | | 1 | | 7 | | 20 | | 29 | | 20 | | 7 | | 1 | | | | |
| | | 1 | | 8 | | 27 | | 49 | | 49 | | 27 | | 8 | | 1 | | | |
| | 1 | | 9 | | 35 | | 76 | | 99 | | 76 | | 35 | | 9 | | 1 | | |
| 1 | | 10 | | 44 | | 111 | | 175 | | 175 | | 111 | | 44 | | 10 | | 1 | |
| 1 | | 11 | | 54 | | 155 | | 286 | | 351 | | 286 | | 155 | | 54 | | 11 | | 1 |
A013580 formatted as a square array:
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | |
| 1 | 4 | 9 | 14 | 20 | 27 | 35 | 44 | 54 | | |
| 1 | 5 | 14 | 29 | 49 | 76 | 111 | 155 | | | |
| 1 | 6 | 20 | 49 | 99 | 175 | 286 | | | | |
| 1 | 7 | 27 | 76 | 175 | 351 | | | | | |
| 1 | 8 | 35 | 111 | 286 | | | | | | |
| 1 | 9 | 44 | 155 | | | | | | | |
| 1 | 10 | 54 | | | | | | | | |
| 1 | 11 | | | | | | | | | |
| 1 | | | | | | | | | | |
A013580 formatted as an upper right triangle:
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| 1 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| | 1 | 4 | 9 | 14 | 20 | 27 | 35 | 44 | 54 |
| | | 1 | 5 | 14 | 29 | 49 | 76 | 111 | 155 |
| | | | 1 | 6 | 20 | 49 | 99 | 175 | 286 |
| | | | | 1 | 7 | 27 | 76 | 175 | 351 |
| | | | | | 1 | 8 | 35 | 111 | 286 |
| | | | | | | 1 | 9 | 44 | 155 |
| | | | | | | | 1 | 10 | 54 |
| | | | | | | | | 1 | 11 |
| | | | | | | | | | 1 |
|
