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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 24 |
| 4 | 105 |
| 5 | 425 |
| 6 | 1977 |
| 7 | 8631 |
| 8 | 41261 |
| 9 | 187676 |
| 10 | 910559 |
| 11 | 4246915 |
| 12 | 20787681 |
| 13 | 98571981 |
| 14 | 485219638 |
| 15 | 2327411883 |
| 16 | 11500348994 |
| 17 | 55622208284 |
| 18 | 275578607198 |
| 19 | 1341114592732 |
| 20 | 6657370299054 |
| 21 | 32551554792627 |
| 22 | 161820037945969 |
| 23 | 794141060496540 |
| 24 | 3952133603604302 |
| 25 | 19451910424970058 |
| 26 | 96886232243443329 |
[1,2,7,24,105,425,1977,8631,41261,187676,910559, 4246915,20787681,98571981,485219638,2327411883, 11500348994,55622208284,275578607198, 1341114592732,6657370299054,32551554792627, 161820037945969,794141060496540,3952133603604302, 19451910424970058,96886232243443329] |