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| n | a(n) |
|---|---|
| 1 | 117 |
| 2 | 405 |
| 3 | 1489 |
| 4 | 5077 |
| 5 | 17447 |
| 6 | 60237 |
| 7 | 206739 |
| 8 | 711741 |
| 9 | 2455031 |
| 10 | 8451157 |
| 11 | 29078117 |
| 12 | 100127001 |
| 13 | 344830161 |
| 14 | 1187280665 |
| 15 | 4087598971 |
| 16 | 14073866371 |
| 17 | 48459148689 |
| 18 | 166851565139 |
| 19 | 574482172185 |
| 20 | 1977991833471 |
| 21 | 6810453196653 |
| 22 | 23449166058609 |
[117,405,1489,5077,17447,60237,206739,711741, 2455031,8451157,29078117,100127001,344830161, 1187280665,4087598971,14073866371,48459148689, 166851565139,574482172185,1977991833471, 6810453196653,23449166058609] |