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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 63 |
| 10 | 109 |
| 11 | 781 |
| 12 | 1575 |
| 13 | 12401 |
| 14 | 27045 |
| 15 | 346129 |
| 16 | 858707 |
| 17 | 43136869 |
| 18 | 130994019 |
| 19 | 11875535419 |
| 20 | 43413437829 |
| 21 | 3832077399895 |
| 22 | 16507726912431 |
| 23 | 1910337965009389 |
| 24 | 9542878365158887 |
| 25 | 2142686650051542137 |
[1,1,1,1,1,1,1,1,63,109,781,1575,12401,27045, 346129,858707,43136869,130994019,11875535419, 43413437829,3832077399895,16507726912431, 1910337965009389,9542878365158887, 2142686650051542137] |