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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 45 |
| 5 | 229 |
| 6 | 1379 |
| 7 | 9654 |
| 8 | 77234 |
| 9 | 695111 |
| 10 | 6951114 |
| 11 | 76462260 |
| 12 | 917547121 |
| 13 | 11928112585 |
| 14 | 166993576197 |
| 15 | 2504903642958 |
| 16 | 40078458287343 |
| 17 | 681333790884832 |
| 18 | 12264008235926983 |
| 19 | 233016156482612677 |
| 20 | 4660323129652253541 |
[1,3,11,45,229,1379,9654,77234,695111,6951114, 76462260,917547121,11928112585,166993576197, 2504903642958,40078458287343,681333790884832, 12264008235926983,233016156482612677, 4660323129652253541] |