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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 29 |
| 4 | 93 |
| 5 | 297 |
| 6 | 949 |
| 7 | 3195 |
| 8 | 10701 |
| 9 | 35675 |
| 10 | 118761 |
| 11 | 412065 |
| 12 | 1420297 |
| 13 | 4867545 |
| 14 | 16663185 |
| 15 | 58759435 |
| 16 | 206130225 |
| 17 | 719682435 |
| 18 | 2508537225 |
| 19 | 8956415877 |
| 20 | 31817261421 |
| 21 | 112516001801 |
| 22 | 397401991437 |
| 23 | 1429566660819 |
| 24 | 5122383513405 |
| 25 | 18286465588971 |
[3,9,29,93,297,949,3195,10701,35675,118761,412065, 1420297,4867545,16663185,58759435,206130225, 719682435,2508537225,8956415877,31817261421, 112516001801,397401991437,1429566660819, 5122383513405,18286465588971] |