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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 69 |
| 5 | 265 |
| 6 | 1153 |
| 7 | 4801 |
| 8 | 21203 |
| 9 | 91055 |
| 10 | 408161 |
| 11 | 1795037 |
| 12 | 8126131 |
| 13 | 36277181 |
| 14 | 165401729 |
| 15 | 746407191 |
| 16 | 3422278411 |
| 17 | 15570552767 |
| 18 | 71713302271 |
| 19 | 328341604021 |
| 20 | 1517767537579 |
| 21 | 6983968845017 |
| 22 | 32382943834625 |
| 23 | 149619923979041 |
| 24 | 695566730093951 |
| 25 | 3224633528854023 |
| 26 | 15024750966474325 |
| 27 | 69853040121425677 |
[1,1,5,17,69,265,1153,4801,21203,91055,408161, 1795037,8126131,36277181,165401729,746407191, 3422278411,15570552767,71713302271,328341604021, 1517767537579,6983968845017,32382943834625, 149619923979041,695566730093951,3224633528854023, 15024750966474325,69853040121425677] |