A281891 as a triangular array
| | | | | | | | | | 1 |
| | | | | | | | | | 0 | | 1 |
| | | | | | | | | 0 | | 1 | | 1 |
| | | | | | | | 0 | | 1 | | 4 | | 1 |
| | | | | | | 0 | | 1 | | 14 | | 22 | | 1 |
| | | | | | 0 | | 1 | | 46 | | 412 | | 162 | | 1 |
| | | | | 0 | | 1 | | 146 | | 7072 | | 22164 | | 1830 | | 1 |
| | | | 0 | | 1 | | 454 | | 115432 | | 2744088 | | 2822340 | | 24270 | | 1 |
| | | 0 | | 1 | | 1394 | | 1827592 | | 319881696 | | 3913037880 | | 496348740 | | 418350 | | 1 |
| | 0 | | 1 | | 4246 | | 28390552 | | 35924741232 | | 5079363328560 | | 9082206410040 | | 147569907780 | | 8040810 | | 1 |
|
A281891 as a square array
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
| | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | 1 | 4 | 14 | 46 | 146 | 454 | 1394 | 4246
| | 1 | 22 | 412 | 7072 | 115432 | 1827592 | 28390552
| | 1 | 162 | 22164 | 2744088 | 319881696 | 35924741232
| | 1 | 1830 | 2822340 | 3913037880 | 5079363328560
| | 1 | 24270 | 496348740 | 9082206410040
| | 1 | 418350 | 147569907780
| | 1 | 8040810
| | 1
|
A281891 as an upper right triangle
| 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0
| | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | | 1 | 4 | 14 | 46 | 146 | 454 | 1394 | 4246
| | | | 1 | 22 | 412 | 7072 | 115432 | 1827592 | 28390552
| | | | | 1 | 162 | 22164 | 2744088 | 319881696 | 35924741232
| | | | | | 1 | 1830 | 2822340 | 3913037880 | 5079363328560
| | | | | | | 1 | 24270 | 496348740 | 9082206410040
| | | | | | | | 1 | 418350 | 147569907780
| | | | | | | | | 1 | 8040810
| | | | | | | | | | 1
|
|
