A131818 formatted as a triangular array:
| | | | | | | | | 1 | | | | | | | | | |
| | | | | | | | 2 | | 2 | | | | | | | | |
| | | | | | | 3 | | 2 | | 3 | | | | | | | |
| | | | | | 4 | | 2 | | 3 | | 4 | | | | | | |
| | | | | 5 | | 2 | | 3 | | 4 | | 5 | | | | | |
| | | | 6 | | 2 | | 3 | | 4 | | 5 | | 6 | | | | |
| | | 7 | | 2 | | 3 | | 4 | | 5 | | 6 | | 7 | | | |
| | 8 | | 2 | | 3 | | 4 | | 5 | | 6 | | 7 | | 8 | | |
| 9 | | 2 | | 3 | | 4 | | 5 | | 6 | | 7 | | 8 | | 9 | |
| 10 | | 2 | | 3 | | 4 | | 5 | | 6 | | 7 | | 8 | | 9 | | 10 |
A131818 formatted as a square array:
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | |
| 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 | | |
| 4 | 4 | 4 | 4 | 4 | 4 | 4 | | | |
| 5 | 5 | 5 | 5 | 5 | 5 | | | | |
| 6 | 6 | 6 | 6 | 6 | | | | | |
| 7 | 7 | 7 | 7 | | | | | | |
| 8 | 8 | 8 | | | | | | | |
| 9 | 9 | | | | | | | | |
| 10 | | | | | | | | | |
A131818 formatted as an upper right triangle:
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
| | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
| | | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
| | | | 5 | 5 | 5 | 5 | 5 | 5 |
| | | | | 6 | 6 | 6 | 6 | 6 |
| | | | | | 7 | 7 | 7 | 7 |
| | | | | | | 8 | 8 | 8 |
| | | | | | | | 9 | 9 |
| | | | | | | | | 10 |
|
