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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 15 |
| 5 | 30 |
| 6 | 59 |
| 7 | 115 |
| 8 | 225 |
| 9 | 443 |
| 10 | 872 |
| 11 | 1715 |
| 12 | 3375 |
| 13 | 6642 |
| 14 | 13072 |
| 15 | 25725 |
| 16 | 50625 |
| 17 | 99630 |
| 18 | 196070 |
| 19 | 385864 |
| 20 | 759375 |
| 21 | 1494443 |
| 22 | 2941047 |
| 23 | 5787950 |
| 24 | 11390625 |
| 25 | 22416633 |
| 26 | 44115701 |
| 27 | 86819244 |
| 28 | 170859375 |
[1,2,4,8,15,30,59,115,225,443,872,1715,3375,6642, 13072,25725,50625,99630,196070,385864,759375, 1494443,2941047,5787950,11390625,22416633, 44115701,86819244,170859375] |