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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 4 |
| 3 | 2 |
| 4 | 62 |
| 5 | 221 |
| 6 | 301 |
| 7 | 1062 |
| 8 | 860 |
| 9 | 21189 |
| 10 | 35835 |
| 11 | 116119 |
| 12 | 317168 |
| 13 | 3000313 |
[2,4,2,62,221,301,1062,860,21189,35835,116119, 317168,3000313] |