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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 9 |
| 5 | 45 |
| 6 | 165 |
| 7 | 1605 |
| 8 | 6645 |
| 9 | 82245 |
| 10 | 626565 |
| 11 | 7430565 |
| 12 | 47347365 |
| 13 | 1294747365 |
| 14 | 7521768165 |
| 15 | 166051339365 |
| 16 | 2617940779365 |
| 17 | 45296384587365 |
| 18 | 400983812683365 |
| 19 | 16124008954507365 |
| 20 | 137769109363339365 |
| 21 | 6031874478387211365 |
| 22 | 98938319915632651365 |
| 23 | 1994173630452264715365 |
| 24 | 27846190369337241355365 |
| 25 | 1807180003160859492619365 |
[1,1,3,9,45,165,1605,6645,82245,626565,7430565, 47347365,1294747365,7521768165,166051339365, 2617940779365,45296384587365,400983812683365, 16124008954507365,137769109363339365, 6031874478387211365,98938319915632651365, 1994173630452264715365,27846190369337241355365, 1807180003160859492619365] |