A026648 as a triangular array
| | | | | | | | | | | | 1 |
| | | | | | | | | | | | 1 | | 1 |
| | | | | | | | | | | 1 | | 3 | | 1 |
| | | | | | | | | | 1 | | 4 | | 4 | | 1 |
| | | | | | | | | 1 | | 6 | | 8 | | 6 | | 1 |
| | | | | | | | 1 | | 7 | | 14 | | 14 | | 7 | | 1 |
| | | | | | | 1 | | 9 | | 21 | | 36 | | 21 | | 9 | | 1 |
| | | | | | 1 | | 10 | | 30 | | 57 | | 57 | | 30 | | 10 | | 1 |
| | | | | 1 | | 12 | | 40 | | 108 | | 114 | | 108 | | 40 | | 12 | | 1 |
| | | | 1 | | 13 | | 52 | | 148 | | 222 | | 222 | | 148 | | 52 | | 13 | | 1 |
| | | 1 | | 15 | | 65 | | 240 | | 370 | | 558 | | 370 | | 240 | | 65 | | 15 | | 1 |
| | 1 | | 16 |
|
A026648 as a square array
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | 1 | 3 | 4 | 6 | 7 | 9 | 10 | 12 | 13 | 15 | 16
| | 1 | 4 | 8 | 14 | 21 | 30 | 40 | 52 | 65
| | 1 | 6 | 14 | 36 | 57 | 108 | 148 | 240
| | 1 | 7 | 21 | 57 | 114 | 222 | 370
| | 1 | 9 | 30 | 108 | 222 | 558
| | 1 | 10 | 40 | 148 | 370
| | 1 | 12 | 52 | 240
| | 1 | 13 | 65
| | 1 | 15
| | 1
|
A026648 as an upper right triangle
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1
| | 1 | 3 | 4 | 6 | 7 | 9 | 10 | 12 | 13 | 15 | 16
| | | 1 | 4 | 8 | 14 | 21 | 30 | 40 | 52 | 65
| | | | 1 | 6 | 14 | 36 | 57 | 108 | 148 | 240
| | | | | 1 | 7 | 21 | 57 | 114 | 222 | 370
| | | | | | 1 | 9 | 30 | 108 | 222 | 558
| | | | | | | 1 | 10 | 40 | 148 | 370
| | | | | | | | 1 | 12 | 52 | 240
| | | | | | | | | 1 | 13 | 65
| | | | | | | | | | 1 | 15
| | | | | | | | | | | 1
| | | | | | | | | | |
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