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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 21 |
| 5 | 47 |
| 6 | 99 |
| 7 | 205 |
| 8 | 417 |
| 9 | 843 |
| 10 | 1695 |
| 11 | 3401 |
| 12 | 6813 |
| 13 | 13639 |
| 14 | 27291 |
| 15 | 54597 |
| 16 | 109209 |
| 17 | 218435 |
| 18 | 436887 |
| 19 | 873793 |
| 20 | 1747605 |
| 21 | 3495231 |
| 22 | 6990483 |
| 23 | 13980989 |
| 24 | 27962001 |
| 25 | 55924027 |
| 26 | 111848079 |
| 27 | 223696185 |
| 28 | 447392397 |
| 29 | 894784823 |
| 30 | 1789569675 |
| 31 | 3579139381 |
| 32 | 7158278793 |
| 33 | 14316557619 |
[0,1,3,9,21,47,99,205,417,843,1695,3401,6813, 13639,27291,54597,109209,218435,436887,873793, 1747605,3495231,6990483,13980989,27962001, 55924027,111848079,223696185,447392397,894784823, 1789569675,3579139381,7158278793,14316557619] |