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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 11 |
| 3 | 36 |
| 4 | 115 |
| 5 | 387 |
| 6 | 1280 |
| 7 | 4237 |
| 8 | 14026 |
| 9 | 46454 |
| 10 | 153800 |
| 11 | 509255 |
| 12 | 1686210 |
| 13 | 5583282 |
| 14 | 18486920 |
| 15 | 61212645 |
| 16 | 202682982 |
| 17 | 671109638 |
| 18 | 2222130975 |
| 19 | 7357763936 |
| 20 | 24362510288 |
| 21 | 80667430752 |
| 22 | 267100323021 |
| 23 | 884403804216 |
| 24 | 2928375674093 |
| 25 | 9696231573791 |
[3,11,36,115,387,1280,4237,14026,46454,153800, 509255,1686210,5583282,18486920,61212645, 202682982,671109638,2222130975,7357763936, 24362510288,80667430752,267100323021,884403804216, 2928375674093,9696231573791] |