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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 37 |
| 5 | 141 |
| 6 | 871 |
| 7 | 4243 |
| 8 | 42057 |
| 9 | 285337 |
| 10 | 3008971 |
| 11 | 23292831 |
| 12 | 295839853 |
| 13 | 2733811237 |
| 14 | 35818366767 |
| 15 | 360892885291 |
| 16 | 8394097115281 |
| 17 | 113063153955633 |
| 18 | 2347668770502547 |
| 19 | 32362689647446327 |
| 20 | 744513384520939701 |
| 21 | 11439249110436735421 |
| 22 | 245772094687992577783 |
| 23 | 3860080495614830875587 |
[1,1,3,7,37,141,871,4243,42057,285337,3008971, 23292831,295839853,2733811237,35818366767, 360892885291,8394097115281,113063153955633, 2347668770502547,32362689647446327, 744513384520939701,11439249110436735421, 245772094687992577783,3860080495614830875587] |