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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 1 |
| 10 | 8 |
| 11 | 79 |
| 12 | 754 |
| 13 | 7240 |
| 14 | 72828 |
| 15 | 784390 |
| 16 | 9099151 |
| 17 | 112170248 |
| 18 | 1434040695 |
| 19 | 18548321329 |
| 20 | 238131628435 |
| 21 | 2996684899641 |
| 22 | 36690482155548 |
| 23 | 435346012682054 |
| 24 | 4996906225153071 |
| 25 | 55453365806920084 |
[0,0,0,0,0,0,0,0,1,8,79,754,7240,72828,784390, 9099151,112170248,1434040695,18548321329, 238131628435,2996684899641,36690482155548, 435346012682054,4996906225153071, 55453365806920084] |