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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 3 |
| 4 | 1 |
| 5 | 5 |
| 6 | 141 |
| 7 | 742 |
| 8 | 6120 |
| 9 | 43888 |
| 10 | 300232 |
| 11 | 3074478 |
| 12 | 28901797 |
| 13 | 290411147 |
| 14 | 3175037698 |
| 15 | 34951274416 |
| 16 | 399750066121 |
| 17 | 4814421349467 |
| 18 | 59532792202344 |
| 19 | 768079420764884 |
| 20 | 10247011240209066 |
| 21 | 140144002390928732 |
| 22 | 1978092111496441512 |
| 23 | 28633995987157024399 |
[1,1,0,3,1,5,141,742,6120,43888,300232,3074478, 28901797,290411147,3175037698,34951274416, 399750066121,4814421349467,59532792202344, 768079420764884,10247011240209066, 140144002390928732,1978092111496441512, 28633995987157024399] |