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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | -1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 3 |
| 6 | 5 |
| 7 | 11 |
| 8 | 27 |
| 9 | 65 |
| 10 | 154 |
| 11 | 371 |
| 12 | 917 |
| 13 | 2303 |
| 14 | 5828 |
| 15 | 14839 |
| 16 | 38049 |
| 17 | 98237 |
| 18 | 255106 |
| 19 | 665655 |
| 20 | 1744318 |
| 21 | 4588881 |
| 22 | 12115727 |
| 23 | 32092597 |
| 24 | 85259160 |
| 25 | 227117149 |
| 26 | 606512641 |
| 27 | 1623412007 |
| 28 | 4354539253 |
| 29 | 11703442343 |
| 30 | 31512560472 |
| 31 | 84996156243 |
| 32 | 229621401075 |
[2,-1,1,2,3,5,11,27,65,154,371,917,2303,5828, 14839,38049,98237,255106,665655,1744318,4588881, 12115727,32092597,85259160,227117149,606512641, 1623412007,4354539253,11703442343,31512560472, 84996156243,229621401075] |