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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 16 |
| 6 | 61 |
| 7 | 272 |
| 8 | 1385 |
| 9 | 7936 |
| 10 | 50521 |
| 11 | 353791 |
| 12 | 2702767 |
| 13 | 22368251 |
| 14 | 199360995 |
| 15 | 1903757268 |
| 16 | 19391512295 |
| 17 | 209865342434 |
| 18 | 2404879677510 |
| 19 | 29088885104489 |
| 20 | 370371188272931 |
| 21 | 4951498052966308 |
| 22 | 69348874393874527 |
| 23 | 1015423886503257017 |
| 24 | 15514534163575397655 |
[1,1,1,2,5,16,61,272,1385,7936,50521,353791, 2702767,22368251,199360995,1903757268,19391512295, 209865342434,2404879677510,29088885104489, 370371188272931,4951498052966308, 69348874393874527,1015423886503257017, 15514534163575397655] |