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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 17 |
| 4 | 69 |
| 5 | 277 |
| 6 | 1199 |
| 7 | 4997 |
| 8 | 22323 |
| 9 | 96197 |
| 10 | 433435 |
| 11 | 1914391 |
| 12 | 8686795 |
| 13 | 38913039 |
| 14 | 177843391 |
| 15 | 804285853 |
| 16 | 3695136351 |
| 17 | 16839549393 |
| 18 | 77665053029 |
| 19 | 356072649163 |
| 20 | 1647634680213 |
| 21 | 7589339987379 |
| 22 | 35217751634367 |
| 23 | 162838988949557 |
| 24 | 757466254449869 |
| 25 | 3513570095624009 |
| 26 | 16377908690599267 |
| 27 | 76175870755112467 |
[1,1,5,17,69,277,1199,4997,22323,96197,433435, 1914391,8686795,38913039,177843391,804285853, 3695136351,16839549393,77665053029,356072649163, 1647634680213,7589339987379,35217751634367, 162838988949557,757466254449869,3513570095624009, 16377908690599267,76175870755112467] |