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| n | a(n) |
|---|---|
| 1 | 15 |
| 2 | 101 |
| 3 | 463 |
| 4 | 2119 |
| 5 | 9012 |
| 6 | 35116 |
| 7 | 132342 |
| 8 | 493096 |
| 9 | 1811125 |
| 10 | 6520133 |
| 11 | 23029880 |
| 12 | 80160412 |
| 13 | 275921198 |
[15,101,463,2119,9012,35116,132342,493096,1811125, 6520133,23029880,80160412,275921198] |