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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 17 |
| 5 | 45 |
| 6 | 131 |
| 7 | 419 |
| 8 | 1465 |
| 9 | 5561 |
| 10 | 22755 |
| 11 | 99727 |
| 12 | 465537 |
| 13 | 2303829 |
| 14 | 12037571 |
| 15 | 66174411 |
| 16 | 381560425 |
| 17 | 2301307841 |
| 18 | 14483421859 |
| 19 | 94909491607 |
| 20 | 646309392369 |
| 21 | 4565559980989 |
| 22 | 33401808977411 |
| 23 | 252713264780595 |
| 24 | 1974606909857945 |
[1,3,7,17,45,131,419,1465,5561,22755,99727,465537, 2303829,12037571,66174411,381560425,2301307841, 14483421859,94909491607,646309392369, 4565559980989,33401808977411,252713264780595, 1974606909857945] |