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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 36 |
| 5 | 131 |
| 6 | 476 |
| 7 | 1728 |
| 8 | 6272 |
| 9 | 22765 |
| 10 | 82629 |
| 11 | 299915 |
| 12 | 1088589 |
| 13 | 3951206 |
| 14 | 14341527 |
| 15 | 52054840 |
| 16 | 188941273 |
| 17 | 685792227 |
| 18 | 2489191330 |
| 19 | 9034913540 |
| 20 | 32793647355 |
| 21 | 119029728628 |
| 22 | 432037221840 |
| 23 | 1568147413312 |
| 24 | 5691839002677 |
| 25 | 20659429692245 |
| 26 | 74986666876571 |
| 27 | 272175964826781 |
[1,3,10,36,131,476,1728,6272,22765,82629,299915, 1088589,3951206,14341527,52054840,188941273, 685792227,2489191330,9034913540,32793647355, 119029728628,432037221840,1568147413312, 5691839002677,20659429692245,74986666876571, 272175964826781] |