A209561 as a triangular array
| | | | | | | | | | | | 1 |
| | | | | | | | | | | | 1 | | 1 |
| | | | | | | | | | | 2 | | 2 | | 1 |
| | | | | | | | | | 3 | | 4 | | 3 | | 1 |
| | | | | | | | | 4 | | 7 | | 7 | | 4 | | 1 |
| | | | | | | | 5 | | 11 | | 14 | | 11 | | 5 | | 1 |
| | | | | | | 6 | | 16 | | 25 | | 25 | | 16 | | 6 | | 1 |
| | | | | | 7 | | 22 | | 41 | | 50 | | 41 | | 22 | | 7 | | 1 |
| | | | | 8 | | 29 | | 63 | | 91 | | 91 | | 63 | | 29 | | 8 | | 1 |
| | | | 9 | | 37 | | 92 | | 154 | | 182 | | 154 | | 92 | | 37 | | 9 | | 1 |
| | | 10 | | 46 | | 129 | | 246 | | 336 | | 336 | | 246 | | 129 | | 46 | | 10 | | 1 |
| | 11 | | 56 | | 175 | | 375 | | 582 | | 672 |
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A209561 as a square array
| 1 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11
| | 1 | 2 | 4 | 7 | 11 | 16 | 22 | 29 | 37 | 46 | 56
| | 1 | 3 | 7 | 14 | 25 | 41 | 63 | 92 | 129 | 175
| | 1 | 4 | 11 | 25 | 50 | 91 | 154 | 246 | 375
| | 1 | 5 | 16 | 41 | 91 | 182 | 336 | 582
| | 1 | 6 | 22 | 63 | 154 | 336 | 672
| | 1 | 7 | 29 | 92 | 246
| | 1 | 8 | 37 | 129
| | 1 | 9 | 46
| | 1 | 10
| | 1
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A209561 as an upper right triangle
| 1 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11
| | 1 | 2 | 4 | 7 | 11 | 16 | 22 | 29 | 37 | 46 | 56
| | | 1 | 3 | 7 | 14 | 25 | 41 | 63 | 92 | 129 | 175
| | | | 1 | 4 | 11 | 25 | 50 | 91 | 154 | 246 | 375
| | | | | 1 | 5 | 16 | 41 | 91 | 182 | 336 | 582
| | | | | | 1 | 6 | 22 | 63 | 154 | 336 | 672
| | | | | | | 1 | 7 | 29 | 92 | 246
| | | | | | | | 1 | 8 | 37 | 129
| | | | | | | | | 1 | 9 | 46
| | | | | | | | | | 1 | 10
| | | | | | | | | | | 1
| | | | | | | | | | |
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