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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 16 |
| 3 | 12 |
| 4 | 166 |
| 5 | 537 |
| 6 | 2573 |
| 7 | 16538 |
| 8 | 83533 |
| 9 | 420801 |
| 10 | 2412733 |
| 11 | 12975515 |
| 12 | 68321766 |
| 13 | 376287484 |
| 14 | 2042163601 |
| 15 | 10949762356 |
| 16 | 59563103680 |
| 17 | 323175890698 |
| 18 | 1744473182106 |
| 19 | 9456860848043 |
| 20 | 51262356984369 |
| 21 | 277339276333524 |
| 22 | 1502217683264205 |
[1,16,12,166,537,2573,16538,83533,420801,2412733, 12975515,68321766,376287484,2042163601, 10949762356,59563103680,323175890698, 1744473182106,9456860848043,51262356984369, 277339276333524,1502217683264205] |