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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 5 |
| 8 | 13 |
| 9 | 49 |
| 10 | 284 |
| 11 | 3937 |
| 12 | 196605 |
| 13 | 56028733 |
| 14 | 220640957641 |
| 15 | 43379336062130626 |
| 16 | 2430489281321503732285663 |
| 17 | 536265482569392926735606762349877841 |
| 18 | 23262840586898349755381222452865322555989091379459449 |
[1,1,1,1,2,3,5,13,49,284,3937,196605,56028733, 220640957641,43379336062130626, 2430489281321503732285663, 536265482569392926735606762349877841, 23262840586898349755381222452865322555989091379459\ 449] |