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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 42 |
| 5 | 161 |
| 6 | 619 |
| 7 | 2381 |
| 8 | 9160 |
| 9 | 35241 |
| 10 | 135583 |
| 11 | 521631 |
| 12 | 2006882 |
| 13 | 7721121 |
| 14 | 29705639 |
| 15 | 114287161 |
| 16 | 439699520 |
| 17 | 1691665681 |
| 18 | 6508382763 |
| 19 | 25039844851 |
| 20 | 96336348522 |
| 21 | 370636962881 |
| 22 | 1425959779059 |
| 23 | 5486126574341 |
| 24 | 21106896023080 |
| 25 | 81205027571321 |
| 26 | 312421897357543 |
[1,3,11,42,161,619,2381,9160,35241,135583,521631, 2006882,7721121,29705639,114287161,439699520, 1691665681,6508382763,25039844851,96336348522, 370636962881,1425959779059,5486126574341, 21106896023080,81205027571321,312421897357543] |