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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 4 |
| 5 | 10 |
| 6 | 21 |
| 7 | 49 |
| 8 | 104 |
| 9 | 227 |
| 10 | 468 |
| 11 | 976 |
| 12 | 1978 |
| 13 | 4030 |
| 14 | 8095 |
| 15 | 16313 |
| 16 | 32656 |
| 17 | 65503 |
| 18 | 130986 |
[1,1,2,4,10,21,49,104,227,468,976,1978,4030,8095, 16313,32656,65503,130986] |