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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 8 |
| 3 | 34 |
| 4 | 144 |
| 5 | 612 |
| 6 | 2613 |
| 7 | 11159 |
| 8 | 47675 |
| 9 | 203696 |
| 10 | 870316 |
| 11 | 3718550 |
| 12 | 15888022 |
| 13 | 67883780 |
| 14 | 290042861 |
| 15 | 1239248291 |
| 16 | 5294859950 |
| 17 | 22623022401 |
| 18 | 96659996189 |
| 19 | 412993219856 |
| 20 | 1764570725956 |
| 21 | 7539372796546 |
| 22 | 32213014377497 |
| 23 | 137634565007885 |
[3,8,34,144,612,2613,11159,47675,203696,870316, 3718550,15888022,67883780,290042861,1239248291, 5294859950,22623022401,96659996189,412993219856, 1764570725956,7539372796546,32213014377497, 137634565007885] |