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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 9 |
| 5 | 27 |
| 6 | 93 |
| 7 | 392 |
| 8 | 1898 |
| 9 | 10493 |
| 10 | 64885 |
| 11 | 443916 |
| 12 | 3326317 |
| 13 | 27085015 |
| 14 | 238073306 |
| 15 | 2246348560 |
| 16 | 22643042325 |
| 17 | 242808804441 |
| 18 | 2759740869777 |
| 19 | 33138397797908 |
| 20 | 419171443909394 |
| 21 | 5570771017483187 |
| 22 | 77603014042711369 |
| 23 | 1130712331125929112 |
| 24 | 17198408830271090233 |
[1,1,2,4,9,27,93,392,1898,10493,64885,443916, 3326317,27085015,238073306,2246348560,22643042325, 242808804441,2759740869777,33138397797908, 419171443909394,5570771017483187, 77603014042711369,1130712331125929112, 17198408830271090233] |