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| n | a(n) |
|---|---|
| 1 | 24 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 9 |
| 11 | 65 |
| 12 | 624 |
| 13 | 5309 |
| 14 | 38578 |
| 15 | 239701 |
| 16 | 1309340 |
| 17 | 6447890 |
| 18 | 29143104 |
| 19 | 122531502 |
| 20 | 484952549 |
| 21 | 1822769330 |
| 22 | 6559659490 |
| 23 | 22756224972 |
| 24 | 76595595448 |
| 25 | 251727333628 |
| 26 | 813474158085 |
| 27 | 2607267986103 |
[24,1,1,1,1,1,1,1,1,9,65,624,5309,38578,239701, 1309340,6447890,29143104,122531502,484952549, 1822769330,6559659490,22756224972,76595595448, 251727333628,813474158085,2607267986103] |