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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 59 |
| 4 | 362 |
| 5 | 2287 |
| 6 | 14719 |
| 7 | 95965 |
| 8 | 631714 |
| 9 | 4189334 |
| 10 | 27946335 |
| 11 | 187319827 |
| 12 | 1260570515 |
| 13 | 8511460908 |
| 14 | 57634550179 |
| 15 | 391232510284 |
| 16 | 2661483301282 |
| 17 | 18140003082945 |
| 18 | 123846214549072 |
| 19 | 846801764644618 |
| 20 | 5797865791444367 |
| 21 | 39745254613927264 |
| 22 | 272762265331208465 |
[1,2,10,59,362,2287,14719,95965,631714,4189334, 27946335,187319827,1260570515,8511460908, 57634550179,391232510284,2661483301282, 18140003082945,123846214549072,846801764644618, 5797865791444367,39745254613927264, 272762265331208465] |