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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 17 |
| 6 | 37 |
| 7 | 85 |
| 8 | 200 |
| 9 | 486 |
| 10 | 1205 |
| 11 | 3047 |
| 12 | 7813 |
| 13 | 20299 |
| 14 | 53272 |
| 15 | 141083 |
| 16 | 376464 |
| 17 | 1011311 |
| 18 | 2732470 |
| 19 | 7421146 |
| 20 | 20247374 |
| 21 | 55469206 |
| 22 | 152524387 |
| 23 | 420807242 |
| 24 | 1164532226 |
| 25 | 3231706871 |
| 26 | 8991343381 |
| 27 | 25075077710 |
| 28 | 70082143979 |
| 29 | 196268698287 |
| 30 | 550695545884 |
| 31 | 1547867058882 |
[1,2,4,8,17,37,85,200,486,1205,3047,7813,20299, 53272,141083,376464,1011311,2732470,7421146, 20247374,55469206,152524387,420807242,1164532226, 3231706871,8991343381,25075077710,70082143979, 196268698287,550695545884,1547867058882] |