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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 16 |
| 6 | 36 |
| 7 | 80 |
| 8 | 193 |
| 9 | 497 |
| 10 | 1392 |
| 11 | 4282 |
| 12 | 14805 |
| 13 | 57875 |
| 14 | 258894 |
| 15 | 1321280 |
| 16 | 7570495 |
| 17 | 47305333 |
| 18 | 311742256 |
| 19 | 2103025726 |
| 20 | 14206632939 |
| 21 | 94726167427 |
| 22 | 618051904983 |
| 23 | 3927156178649 |
| 24 | 24243834619157 |
| 25 | 145277300343585 |
| 26 | 844969890205372 |
| 27 | 4772180415241078 |
| 28 | 26189419064610811 |
| 29 | 139774809119967723 |
[1,2,4,8,16,36,80,193,497,1392,4282,14805,57875, 258894,1321280,7570495,47305333,311742256, 2103025726,14206632939,94726167427,618051904983, 3927156178649,24243834619157,145277300343585, 844969890205372,4772180415241078, 26189419064610811,139774809119967723] |