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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 16 |
| 5 | 30 |
| 6 | 56 |
| 7 | 104 |
| 8 | 195 |
| 9 | 370 |
| 10 | 706 |
| 11 | 1352 |
| 12 | 2588 |
| 13 | 4952 |
| 14 | 9477 |
| 15 | 18157 |
| 16 | 34854 |
| 17 | 67040 |
| 18 | 129191 |
| 19 | 249346 |
| 20 | 481877 |
| 21 | 932352 |
| 22 | 1806008 |
| 23 | 3502388 |
| 24 | 6800114 |
| 25 | 13218020 |
| 26 | 25721341 |
| 27 | 50103831 |
| 28 | 97694970 |
| 29 | 190666603 |
| 30 | 372442573 |
| 31 | 728131340 |
| 32 | 1424656550 |
| 33 | 2789619644 |
[1,2,4,8,16,30,56,104,195,370,706,1352,2588,4952, 9477,18157,34854,67040,129191,249346,481877, 932352,1806008,3502388,6800114,13218020,25721341, 50103831,97694970,190666603,372442573,728131340, 1424656550,2789619644] |