A049020 formatted as a triangular array:
| | | | | | | | 1 | | | | | | | | |
| | | | | | | 1 | | 1 | | | | | | | |
| | | | | | 2 | | 3 | | 1 | | | | | | |
| | | | | 5 | | 10 | | 6 | | 1 | | | | | |
| | | | 15 | | 37 | | 31 | | 10 | | 1 | | | | |
| | | 52 | | 151 | | 160 | | 75 | | 15 | | 1 | | | |
| | 203 | | 674 | | 856 | | 520 | | 155 | | 21 | | 1 | | |
| 877 | | 3263 | | 4802 | | 3556 | | 1400 | | 287 | | 28 | | 1 | |
| 4140 | | 17007 | | 28337 | | 24626 | | 11991 | | 3290 | | 490 | | 36 | | 1 |
A049020 formatted as a square array:
| 1 | 1 | 2 | 5 | 15 | 52 | 203 | 877 | 4140 |
| 1 | 3 | 10 | 37 | 151 | 674 | 3263 | 17007 | |
| 1 | 6 | 31 | 160 | 856 | 4802 | 28337 | | |
| 1 | 10 | 75 | 520 | 3556 | 24626 | | | |
| 1 | 15 | 155 | 1400 | 11991 | | | | |
| 1 | 21 | 287 | 3290 | | | | | |
| 1 | 28 | 490 | | | | | | |
| 1 | 36 | | | | | | | |
| 1 | | | | | | | | |
A049020 formatted as an upper right triangle:
| 1 | 1 | 2 | 5 | 15 | 52 | 203 | 877 | 4140 |
| 1 | 3 | 10 | 37 | 151 | 674 | 3263 | 17007 |
| | 1 | 6 | 31 | 160 | 856 | 4802 | 28337 |
| | | 1 | 10 | 75 | 520 | 3556 | 24626 |
| | | | 1 | 15 | 155 | 1400 | 11991 |
| | | | | 1 | 21 | 287 | 3290 |
| | | | | | 1 | 28 | 490 |
| | | | | | | 1 | 36 |
| | | | | | | | 1 |
|
