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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 15 |
| 3 | 43 |
| 4 | 99 |
| 5 | 211 |
| 6 | 435 |
| 7 | 883 |
| 8 | 1779 |
| 9 | 3571 |
| 10 | 7155 |
| 11 | 14323 |
| 12 | 28659 |
| 13 | 57331 |
| 14 | 114675 |
| 15 | 229363 |
| 16 | 458739 |
| 17 | 917491 |
| 18 | 1834995 |
| 19 | 3670003 |
| 20 | 7340019 |
| 21 | 14680051 |
| 22 | 29360115 |
| 23 | 58720243 |
| 24 | 117440499 |
| 25 | 234881011 |
| 26 | 469762035 |
| 27 | 939524083 |
| 28 | 1879048179 |
| 29 | 3758096371 |
[1,15,43,99,211,435,883,1779,3571,7155,14323, 28659,57331,114675,229363,458739,917491,1834995, 3670003,7340019,14680051,29360115,58720243, 117440499,234881011,469762035,939524083, 1879048179,3758096371] |