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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 31 |
| 4 | 129 |
| 5 | 531 |
| 6 | 2129 |
| 7 | 8351 |
| 8 | 32177 |
| 9 | 122211 |
| 10 | 458801 |
| 11 | 1706015 |
| 12 | 6293169 |
| 13 | 23057651 |
| 14 | 83992313 |
| 15 | 304424639 |
| 16 | 1098525761 |
| 17 | 3948727555 |
| 18 | 14145206209 |
| 19 | 50515602111 |
| 20 | 179904080257 |
| 21 | 639103899411 |
| 22 | 2265253438745 |
| 23 | 8012421964063 |
[1,3,9,31,129,531,2129,8351,32177,122211,458801, 1706015,6293169,23057651,83992313,304424639, 1098525761,3948727555,14145206209,50515602111, 179904080257,639103899411,2265253438745, 8012421964063] |