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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 8 |
| 3 | 29 |
| 4 | 115 |
| 5 | 452 |
| 6 | 1779 |
| 7 | 7001 |
| 8 | 27552 |
| 9 | 108429 |
| 10 | 426715 |
| 11 | 1679308 |
| 12 | 6608803 |
| 13 | 26008497 |
| 14 | 102354680 |
| 15 | 402809917 |
| 16 | 1585231171 |
| 17 | 6238570004 |
| 18 | 24551470099 |
| 19 | 96620649225 |
| 20 | 380244026896 |
| 21 | 1496424637485 |
| 22 | 5889077900715 |
| 23 | 23176067575964 |
[1,1,8,29,115,452,1779,7001,27552,108429,426715, 1679308,6608803,26008497,102354680,402809917, 1585231171,6238570004,24551470099,96620649225, 380244026896,1496424637485,5889077900715, 23176067575964] |