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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 38 |
| 6 | 115 |
| 7 | 377 |
| 8 | 1267 |
| 9 | 4446 |
| 10 | 15970 |
| 11 | 58741 |
| 12 | 219765 |
| 13 | 834779 |
| 14 | 3208732 |
| 15 | 12461304 |
| 16 | 48809233 |
| 17 | 192596729 |
| 18 | 764814458 |
| 19 | 3054101548 |
| 20 | 12255774481 |
| 21 | 49396159564 |
| 22 | 199867069373 |
| 23 | 811554088996 |
| 24 | 3305812070784 |
[2,2,5,13,38,115,377,1267,4446,15970,58741,219765, 834779,3208732,12461304,48809233,192596729, 764814458,3054101548,12255774481,49396159564, 199867069373,811554088996,3305812070784] |