A061554 as a triangular array
| | | | | | | | | | | | 1 |
| | | | | | | | | | | | 1 | | 1 |
| | | | | | | | | | | 2 | | 1 | | 1 |
| | | | | | | | | | 3 | | 3 | | 1 | | 1 |
| | | | | | | | | 6 | | 4 | | 4 | | 1 | | 1 |
| | | | | | | | 10 | | 10 | | 5 | | 5 | | 1 | | 1 |
| | | | | | | 20 | | 15 | | 15 | | 6 | | 6 | | 1 | | 1 |
| | | | | | 35 | | 35 | | 21 | | 21 | | 7 | | 7 | | 1 | | 1 |
| | | | | 70 | | 56 | | 56 | | 28 | | 28 | | 8 | | 8 | | 1 | | 1 |
| | | | 126 | | 126 | | 84 | | 84 | | 36 | | 36 | | 9 | | 9 | | 1 | | 1 |
| | | 252 | | 210 | | 210 | | 120 | | 120 | | 45 | | 45 | | 10 | | 10 | | 1 | | 1 |
| | 462 | | 462 | | 330 | | 330 | | 165 | | 165 | | 55 | | 55 | | 11 | | 11 | | 1 | | 1 |
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A061554 as a square array
| 1 | 1 | 2 | 3 | 6 | 10 | 20 | 35 | 70 | 126 | 252 | 462
| | 1 | 1 | 3 | 4 | 10 | 15 | 35 | 56 | 126 | 210 | 462
| | 1 | 1 | 4 | 5 | 15 | 21 | 56 | 84 | 210 | 330
| | 1 | 1 | 5 | 6 | 21 | 28 | 84 | 120 | 330
| | 1 | 1 | 6 | 7 | 28 | 36 | 120 | 165
| | 1 | 1 | 7 | 8 | 36 | 45 | 165
| | 1 | 1 | 8 | 9 | 45 | 55
| | 1 | 1 | 9 | 10 | 55
| | 1 | 1 | 10 | 11
| | 1 | 1 | 11
| | 1 | 1
| | 1
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A061554 as an upper right triangle
| 1 | 1 | 2 | 3 | 6 | 10 | 20 | 35 | 70 | 126 | 252 | 462
| | 1 | 1 | 3 | 4 | 10 | 15 | 35 | 56 | 126 | 210 | 462
| | | 1 | 1 | 4 | 5 | 15 | 21 | 56 | 84 | 210 | 330
| | | | 1 | 1 | 5 | 6 | 21 | 28 | 84 | 120 | 330
| | | | | 1 | 1 | 6 | 7 | 28 | 36 | 120 | 165
| | | | | | 1 | 1 | 7 | 8 | 36 | 45 | 165
| | | | | | | 1 | 1 | 8 | 9 | 45 | 55
| | | | | | | | 1 | 1 | 9 | 10 | 55
| | | | | | | | | 1 | 1 | 10 | 11
| | | | | | | | | | 1 | 1 | 11
| | | | | | | | | | | 1 | 1
| | | | | | | | | | | | 1
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